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Decay (Co-Op) Mission Walkthrough by Evil Nep Brothers

Version: 1.1 | Updated: 02/12/02

Game:  Half-Life
System:  Sony Playstation 2

Walkthrough type:  Decay (co-op) missions.

Decay Walkthrough
by John and Josh Cable
(a.k.a. The Evil Nep Brothers)

Version 1.1 -- Written on Tuesday, February 12, 2002.
Copyright Josh and John Cable, 2001.
Do not copy or reproduce without permission.

E-mail address:  creexul@yahoo.com

Version 1.1:  Added info about the bonus mission, plus 
the alien slave weapon in the weapons section.


Table of Contents

1.  Decay Info
  a.  Overview
  b.  Characters
  c.  Weapons
  d.  Enemies

2.  Missions

--One:  Dual Access
--Two:  Hazardous Course
--Three:  Surface Call
--Four:  Resonance
--Five:  Domestic Violence
--Six:  Code Green
--Seven:  Crossfire
--Eight:  Intensity
--Nine:  Rift
--Ten (Bonus):  alien slave mission

3.  Credits


1.  Decay Info

  a.  Overview
A shorter, two player version of Half-Life, where you play as
two female scientists (both equipped with the hazardous 
environment suits).  The Decay mission pack is split up into 
seperate missions.  You can't save during any of the 
missions, so you have to complete each mission completly 
before you can save.  If one of the pair dies, the mission 
ends in failure and you must start the mission from the 
very beginning.  They're not really long, but you may need a 
few tries before being able to get through a mission.  Also, 
don't worry about carrying low health into the next mission.  
You automatically get a health and armor (and ammo) recharge 
after each mission is completed and the next one starts.

The two-player ability is optional, and in order to switch 
between the two characters in one-player mode, you push 
select.  The rest of the controls should be the usual stuff 
you've already set up.  If you move one of the characters in 
front of an enemy, in one-player mode, and switch to the 
second character, the first character, controlled by the 
computer, will start attacking.  They won't move or dodge, 
but they turn completely around to fight enemies right behind 
them (sometimes Josh, SOMETIMES).

Two player mode is much better.  First, it's more fun to team 
up and blast baddies left and right in a frenzy.  Second, it's 
easier to just tell your pal what you think you should do.

Even if you've finished Half-Life, on either the PC or the PS2, 
these missions will be quite challanging.  As my brother and I 
played through this, we figured that a walkthrough for the 
Decay missions would indeed be extremely helpful.  We're 
Half-Life masters, and even we got stuck for a little while on 
parts, or got thrashed by monsters.  After you get used to the 
controls and puzzles, you shouldn't have too much trouble 
getting through these levels, with a little help from us.

One important thing to note, the creators of this walkthrough 
preferred playing in 2 player co-op mode, and it is absolutely 

  b.  Characters
There's you two, of course, Dr. Gina Cross or Dr. Colette Green, 
who, under your control, must weave through monsters, traps, and 
other assorted dangers in the ever-crumbling disaster-stricken 
Black Mesa Research Facility.  Along the way, you find the usual 
outfit of security guards and scientists (although much less in 
this than in the actual Half-Life levels).

There are security guards here and there, but you won't be 
able to interact with many of them except one or two.  
They'll add firepower, and they have unlimited ammo so 
don't worry about them running out.  They're officially 
called "Barney" so that's what the security guards will 
be known as from here on.

You'll also meet two main scientists.  Dr. Rosenberg (PC 
veterans might remember him from the Blue Shift expansion 
pack), who will be around to help you in the first couple 
missions, and Dr. Keller, the cripple--UH UH handicapped?  
Dr. Keller is DISABLED, yes, that's right.

There is no "friendly fire," so you can't harm your friend, no 
matter how many times you shoot them.  You can still kill 
yourself with grenades, and OTHER scientists will die if you hit 
them.  If you shoot Rosenberg or Keller even once, the mission 
will fail.  It's pretty easy not to shoot them.  If the temptation 
to kill a scientist is too great, play the normal Half-Life 
missions, where there are plenty of "extra" scientists who AREN'T 
needed to unlock doors, which you can kill in many wonderful ways.

Another thing, try not to get in the way of the AI friendlies 
in this game.  If you block Rosenberg or Keller, or anyone, 
they'll stop.  They should continue moving, but I heard that 
there's an occasional moment where they get stuck, or 
you'll get stuck.  Just try not to be a klutz.

  c.  Weapons
You won't get all the weapons from Half-Life, just the 
basics.  There's always one of each weapon for each player, so 
make sure you get one, and your partner gets the other.  If you 
see two shotguns on a wall, you don't have to creep up to them 
to keep from getting both at once, I'm pretty sure it only lets 
you get one shotgun at a time per player.

Crowbar -- First weapon you get, good for bashing/breaking 
stuff or beating headcrabs.  No secondary fire.  While 
it is strong and has a very fast attack speed, try 
not to run out of ammo.

Beretta -- 9mm handgun.  Not very powerful, but good at 
long range attacking.  If you see an alien slave all the way 
at the other end of a long hallway or room, lock on, make 
sure the crosshair is on them, and pop a few shots 
(remember that they can shoot back at equal range, so you 
aren't much safer).  It can also fire underwater, but you 
shouldn't need that for the Decay missions.  Secondary 
fire fires faster, but with much less accuracy, which is 
good for close range if you emtpy all your other weapons 
and need to keep firing.

SPAS 12 Shotgun -- Single-barrel and double-barrel blasts 
(secondary fire is double-barrel).  Best close range weapon 
in the game.  But (of COURSE!!) terrible long range.  If 
it's the only weapon you have with any ammo, you can kill 
enemies at medium ranges, but it will take far more ammo, 
depending on size and distance of your target.  Also, 
remember that when you start reloading the shotgun, it still 
goes through the normal reloading animations--just that you 
can't see it.  So there will be a short delay before you 
really start reloading shells with this weapon.  Just keep 
that in mind when it comes to the heat of combat.

M4 assault rifle (w/grenade launcher) -- It looks more 
powerful than it is (since it shares the 9mm ammo with 
the Beretta).  The fully automatic fire makes it good for 
taking down anything, though.  It's also equipped with a 
grenade launcher (secondary fire).  The grenades travel 
in an arc, so it helps if you know how far the grenades 
go, so you know how much higher to put your crosshair.  
They're contact grenades, so they explode once they hit a 
wall, the ground, or an enemy.  Massive damage with those 
things.  Save them for alien grunts or human grunts.

.357 Magnum -- High powered pistol.  It's about as strong 
as the shotgun, but also only fires as fast as the shotgun.  
Extremely accurate, though.  You'll want to save this for 
slaves or grunts.  My brother and I don't recommend 
shooting headcrabs with this.  They're too small, and 
you'll most likely miss.  It's a very strong bullet to 
waste on just a lowly headcrab.  No secondary fire, 
except in multiplayer where it zooms in a little bit.

Hand grenades (fragmentation) -- Throw it, it blows up 
after a couple seconds.  Great for taking out the tripod 
machine gun turrets, or tripmines.  Throw them from 
around a corner.  You can throw these at grunts, but if 
they have plenty of space and warning, they'll sometimes 
run away.  However, if there's a lot of grunts bunched up, 
one well-thrown frag grenade will blast them into big 
chunks.  A contact grenade is better for this, though.  
No secondary fire.  If you hold down the grenade button, it'll 
stay in your hand, but the fuse keeps running.  So don't hold 
it in your hand for more than four seconds, or else you'll only 
be able to throw it so far before it blows up in your face.

Rocket Propelled Grenade launcher -- You get this in the 
last mission, and you should only use it on one enemy:  
the big flying alien "jet."  Secondary fire turns the 
aiming laser off, and in the Decay missions I strongly 
recommend AGAINST this.  Leave the laser on, so if you 
lock on to a monster, your target laser will keep tracking 
them and hit them for sure.  Otherwise, it'll just fly 
straight with the laser off.  The only time you should 
have to turn the laser off is in normal Half-Life, when 
you want to fire a rocket at a stationary target, and 
immediately take cover.

Snarks -- Only in the Domestic Violence level, in the grates.  
Sort of hard to get.  These are little alien critters that you 
can throw and they'll run around scratching things spastically 
until they get so overcharged that they explode with a big pop.  They'll 
attack YOU if they can't find any other targets, so be 

Alien Slave Shot -- Available in the bonus mission where you play as an 
alien (or in the normal game in alien mode which is activated via a 
code).  This weapon works a little like the gauss gun in normal Half-
Life where you have to charge your shot to do more damage.  The 
crosshair is your weapon power, and you can see the crosshair changes 
(borders are added to the crosshair) as you keep charging.  You'll only 
need to charge for a second to do full damage and fire a giant green 
electric beam.  When the crosshair is red, it's at full power and you 
should fire immediately, or else the power will backfire and the beam 
will uncharge.  The alternative fire is the slave's claws, which are 
like the crowbar (but cooler of course).

  d.  Enemies

Headcrab -- Small guys that leap and scratch at you.  You 
only need a couple 9mm bullets to put these guys out, but 
they can be pretty hard to hit.  Still, they don't pose 
much of a threat unless you can't kill them quickly.  You 
don't want these guys jumping around tearing you up, or 
worse distracting you from bigger monsters.  A crowbar or 
single-barrel shotgun blast can take care of these guys 
quick.  Headcrabs CAN'T turn you into zombies.

Zombies -- Scientists who get "headcrabbed" turn into 
zombies.  They move slow, but when they get close, they 
swing wide with their big claw arms, and can do some 
mean damage.  You can blast these guys with anything, 
preferably the shotgun.  If you want to save ammo 
(especially early on, which is the most you'll see these 
guys), you can hit and run with the crowbar.  Just don't 
backpedal into the slimy claws of ANOTHER zombie.

Houndeyes -- You'll only see these dog-like creatures in 
about one level.  They charge up a sonic attack, but 
they're extremely weak.  In fact, they seem pretty cute 
and harmless.  Just blast them as soon as possible.  
The shotgun or M4 is best for these.  The only thing to 
worry about the houndeyes is the fact that they're in 
packs, so you have to kill one and turn quick to blast 
the other two flanking you.

Alien Slave -- Weak and cowardly, these guys will die 
quick, and (occasionally) backtrack for some cover.  The 
main threat these guys pose is their big green electric 
shot, which can fry you badly if hit.  You can take cover 
from this attack pretty well, just make sure there's no 
others that have warped in behind you.  If close enough, 
they'll start clawing you, which also does some bad 
damage.  You shouldn't try to get close enough to crowbar 
these guys.  Just shotgun, Magnum, or M4.

Alien Grunt -- These guys are so much more powerful than 
the Alien Slaves that they shouldn't even be in the same 
class/race.  These grunts have a bullet proof armor over 
parts of their body (back, feet, head, the "down there" 
area) which deflects all bullets.  Hit them in their 
soft parts.  They'll still take a couple double-barrel 
blasts from the shotgun, so make sure to keep wailing 
away on these guys until they fall down.  And try not 
to hit them from the back, where their armor covers more 
of their body.  The M4 also works well on these guys.  
There's a very small part of their face that's unarmored, 
and a Magnum bullet will fit in there well, if you can 
get a good shot in it.  It'll do a lot more damage if you 
shoot them in the head.  The main threat from them is 
their "hive hand" which fires seeking bee type shots.  
These shots are weak, but several of them at once while 
you are weak (especially without armor) is a major hazard.

Human Grunts -- The artificial intelligence jewel of 
Half-Life when it was released.  These guys do a lot.  
They come equipped with a shotgun or an M4, and rarely 
you'll find one with contact grenades equipped.  Some 
also have kevlar helmets which will stop any buckshot 
or 9mm bullets.  Just blaze away at their bodies and 
they should go down in a double-barrel blast or a 
hailstorm of M4 bullets.  The Magnum also works very 
well, cutting through a kevlar helmet for an instant 
kill or downing a grunt in 2 body shots.  These guys are 
very likely to backtrack for cover and run from grenades, 
and you almost never fight them or see them when they are 

Osprey -- Giant, yellow-camo colored helicopter that 
drops human grunts.  You only see this once in Decay.  
It's up to you if you want to fight it or not.  Usually 
the best tactic is to run.  For the hardcore, if you 
want to take it down with M4 fire, aim at the rotors on 
both sides (not the wings, JUST the engines attached to 
the rotors at the end of the wings).  You have to shoot 
one until it's constantly pouring black smoke, then start 
blasting the other one.  You have to be able to keep a 
good bead on this, and that means not using the lock-on 
feature and just tracking it with the stick.  It's very 
possible, but it still takes a lot of hits, and you should 
break off an attack once it drops the grunts (you'll need 
to kill them to get more M4 ammo anyway).  This is easier 
in Decay than in Half-Life, since you can have your 
friend help blast the Osprey.  Oh yeah, and when it does 
go down, make sure not to be under it, you'll die 
instantly in the crash.

Alien Controller -- Hovering creatures related to the 
slave and grunt that fire orange-yellowish energy balls 
at you that do some nasty damage.  It fires fast too, 
so it can tear through your armor and melt away your 
health.  These appear in only one mission, but there's 
plenty of them.  The M4 or Magnum should make short 
work of these guys.  If you run out of M4 ammo, you should 
still have at least one full clip in the Beretta to empty 
into these guys.  If all else fails, try the shotgun.  
You won't do much damage with each shot but eventually 
they'll die--stay with single-barrel for this.  Just make 
sure to keep opening fire on them.

Alien "Hovership" -- That's what other people call it, 
but it's more of a large flying creature, a sort of 
purple manta ray.  It's in the Rift mission, and it 
will try to destroy the displacement beacon.  Use the 
rocket launcher until you're out of ammo, then just 
keep firing with the M4, Magnum, or anything (the 
shotgun should still be able to hit it, just not with 
every bit of the buckshot spray).  This hovership is a 
destroyable version of the ones in the Xen missions 
of Half-Life.  You can't kill those ones (you're 
supposed to ride them to certain parts, in case you 
didn't know).  You can kill this one though.


2.  Missions

--One:  Dual Access
Briefing:  "The experiment must be successful.  
Monitor the anti-mass spectrometer and deliver 
anomalous materials to Dr. Freeman."

The introductory mission.

It sounds so easy, but it's a little more complicated than 
this, since it's not JUST running an experiment.  You don't 
have to really monitor anything though.  Just hit a button 
here and there, and push a cart, at first.  Of course, if 
you've played the Half-Life levels, you know what's coming 
up here.  If you can't get past this mission without 
someone leading you by the hand, give up on video games 

Okay, there's a couple things AFTER you have to split up 
your characters which I'll go over.  Once you get to the 
room with Keller, Rosenberg will walk in and they'll have an 
exchange.  Afterwards, you take one player into the 
green-scan room, where they'll go on to the anomalous 
material cart.  Just move down to the end of the hall and 
push a button, and the cart will come up out of the floor.  
You can push against the handholds to edge it forward, or 
push the use key while running into the end of the cart to 
shove it really far.  Don't worry about slamming the cart 
into walls.  As far as I know, it won't explode.

Push the cart into the small space.  Don't sweat when the 
cart elevator gets stuck.  It's supposed to be.  Listen 
to what the scientist says.  Move down the hall with the 
giant red strips into the "test lab" where the two doors 
will open.  Move around and search for something 
malfunctioning.  Very easy to find.  It's just a crowbar 
in some gears.  Go up to the crowbar and you'll pick it 
up.  Your first weapon!

Now switch to the other player.  Move to the OTHER green-scan 
room (not the one the first player goes into).  There's a 
crowbar on the ground in your path.  Keep going, and you'll 
be in a large machine area, with a giant pillar thing in the 
center.  Hit the power switch (use key of course) and then 
then you can use the dial.  After that it's just a matter of 
the scene playing out.  You can't avert the disaster, so 
don't bother.  We recommend that you've at least played a bunch 
of the actual Half-Life levels before this.  You need some of 
the experience when it comes to puzzles and monster battles.  
And so this doesn't spoil the whole part of the story where 
"the facility is struck with a major disaster."

When you wake up, you'll have a player on an upper and lower 
level.  You could have the upper level player just jump over 
the railing, but it's less risky to have them go up the top 
of the collapsed tube, to a small ledge at the end of the 
broken tube, where they can safely jump to the lower level.

There's a half open verticle double door that you have to duck 
under to get through.  This is where the headcrabs show up.  
Use the crowbar.  If you take any damage, there's a health 
charger nearby.  There's a small room at the end of the first 
hall with a dead security guard, and a headcrab that breaks 
the window.  Kill the headcrab, jump through the window, and 
get the guns and armor (one gun for each player, a nice Beretta 
9mm).  Next start moving down the hallways and blast zombies 
and headcrabs you run across.  Keep in mind that there's no 
"tactical reload" so if you empty a gun and change weapons, 
that gun will remain empty until you reload it.

Next you'll see an area where a Barney is fighting houndeyes.  
You can't save him, just keep moving unless you want to watch 
what happens if you get caught in too many houndeye sonic 
blasts.  Move on and after a few more rooms you should find 
yourself back to the original room with Keller and Rosenberg.  
After another exchange, an elevator opens, Rosenberg walks into 
it, and the mission is finished.

Oh yeah, and don't worry about what the briefing says about 
the experiment being successful.  According to you, Valve 
software, and any player of Half-Life and Decay, it should be 
a total failure.  But maybe it would be something else to other 
more mysterious characters... (!)

--Two:  Hazardous Course
Briefing:  "Survivors must call for help.  
Escort Dr. Rosenberg through the training 
area to the surface."

Ever since Opposing Force, Gearbox has loved doing maps where 
you revisit a ruined Hazard Course.  It's the best training 
level in any game, ever, naturally.

You start with Dr. Rosenberg in an elevator, where he tells 
you that your main priority should be helping others escape.  
Well sorry Rosenberg, but you don't do that in Decay, you do 
it in Blue Shift (the former Dreamcast Half Life add-on, 
eventually ported to the PC).  For now, you'll just try to get 
some of this equipment working.

Rosenberg goes up some stairs into another room with an 
elevator--make sure to completely stay out of his way while 
he's running around.  Just stay behind him if you want.  Step 
into the second elevator with him.  The elevator doesn't work, 
so he'll tell you that you have to go through the old hazard 
course to get to an objective.  He opens a couple shutters down 
to the "jump test" area.  Jump-duck through these small 
windows, and complete the three jumps in the test to open the 
next door.

On the other side of the door is a couple headcrabs (9mm will 
take care of them) and the next course room--which is flooded 
with radioactive gunk that will kill you almost immediately if 
you fall into it (you still have a chance to escape as long as 
you get back out in a second, but you'll take massive damage).  
Try pushing the hazard course information button at the front 
of the room there and it'll blow up and collapse (it's a 
no-damage explosion though).  Go up the sides of the room into 
the small windows.  A couple zombies wait for you there, blast 
them (you're close enough to blaze away with the secondary fire 
on the Beretta, on this occasion).  There's 9mm ammo in this 
room.  Stay away with the door that's blocked by fire, you'll 
take (small amounts) of fire damage.  Move back across the 
large pipes to the other side of the room, and then move along 
the side (the side that ISN'T blocked by dangerous steam) and 
go to the door at the end.  The next room is the jump-duck-jump 
test room--and there's a wily little headcrab hiding under the 
second pipe (on the right side).  Kill it, go up the sides of 
the room to the windows, blast the zombie, and go into the 
security door.

Oh yeah, and don't bother with the broken vent you can crawl 
into in that last room.  It leads nowhere, and if you use a 
friend to stack (i.e. they duck, you jump on their head and 
reach a higher position) to the top of the long vent, there's 
nothing up there AND you'll get stuck, and it's EXTREMELY hard 
to get unstuck--it's just not worth it at all so don't even 
remotely try it.  Oh yeah, and there's an electrical wire 
hanging down by the broken vent that will also damage you.

In the security door is a zombie, and in the next room is 
another zombie, it goes without saying that you should be 
blowing away all of these monsters (use the crowbar on the 
zombies if you want, but just make sure not to get clawed by 
them).  Keep moving.  You're in the "duck-jump through pipes" 
test room.  You can't complete the test in the actual test 
area anymore, and there's nothing in there, so you don't even 
have to bother moving out of the observation room area (i.e. 
don't jump through the little windows).  Just keep moving to 
the next door, and head down the ladder (keep looking down to 
keep moving down, and make sure to stay latched onto the ladder 
so you don't fall and take damage).

In this room is a bunch more ammo, a health charger, an armor 
battery, and a smaller room with a security override button.  
Don't push this button until you know what it does:  it closes 
the small room's door, locked in with the security override 
button.  So leave ONE person in this area (preferably the person 
with the least amount of ammo, since there's a pistol and a 
clip right outside the security door inside the hallway--under 
the autogun turrets), have them hit the button, and when the 
Vox announcer says "security override activated," have your 
runner dash out the security door, down the right through the 
hall, keep moving through the left-turn, and then at the end 
of the hall there's a door--don't go in that, right in front 
of that there's a door on the right, THAT'S where you go in.  
If you don't do this fast enough, the security override 
deactivates and about four autosentry turrets come down from 
the ceiling.  Now you CAN kill these, in fact you don't even 
need to avoid them, but if you take the careful way and avoid 
them, you can save yourself a lot of ammo, health, and armor.

Now, your runner should be in a small room with armor and ammo 
(and another health charger).  There's also a funny little 
yellow sign by the door leading back to the security hallway, 
with a little "caution man" being blasted by autoturrets.  
ANYWAY.  What you want to do is move down the stairs in this 
room, but be prepared to backpedal furiously, because about 
three alien slaves beam in.  Carefully pick them off by taking 
cover and firing at them with the Beretta, and when they're 
all dead, go back down and move to the little generator room to 
the right, with a generator lever-switch on the wall.  Hit this 
lever, and the security turrets will turn off, and STAY OFF.  
Have your "stay behind" player run through at this point.

On the other side is the door to the firing range.  To open 
this door, there's a small panel on the right.  Use it, the 
door opens, both players run through, and the Hazard Course 
announcer will go through its usual thing.  When the course 
starts up, the targets start moving around.  You have to hit 
these to move through this room, and there's a headcrab hiding 
in the pipe in the center.  After you start hitting the targets, 
MORE enemies beam in, and a floor will break off where you're 
supposed to enter the next area--and right by the base of this 
ramp, an alien slave will zap in, so blast that and the 
headcrabs.  Oh yeah, you can hit the targets with the crowbar 
if you want, it doesn't matter.  Once all the targets are 
hit, you can move up the ramp made by the broken-off floor, 
and through the gate doors.

In the next room, duck through the broken fence floor, and 
move through a small access down there.  There's a headcrab, 
but by the time you get here, it'll be leaping and screaming 
at you, so hurry up and kill it.  Anyway, keep moving, and 
move ONE BY ONE down the large drop down into the water.  If 
your friend jumps down and lands on you, they'll end up doing 
a LOT of damage to themselves, so make sure to clear out of 
their way.  In this room there's short ladders leading up to 
small side accesses.  There's only one you can reach now, so 
one player has to go up there, hit the spinning wheel marked 
"valve" while the other player runs up the other way while 
the fans are stopped.  The other player should immediately 
move into the door, while the first player should try to run 
up and follow them, but the fans will kick back in and they'll 
only be able to run up so far while being pushed back.  Just 
keep having that person running forward, if they can (if 
they're another REAL person playing, that is).  The player 
already in the next room should take care of the headcrabs 
and such in there first, and grab a shotgun off the wall, and 
then finally hit the lever-switch that will let the other 
player through the air blasting fans and up into their room, 
where they can also grab a shotgun.  You don't have much ammo 
right now so be careful how you use what you have.

The next room is a hallway where alien slaves beam in all over.  
Keep one player back a little bit from the other "pointman" 
player, because the slaves beam in in front AND behind whoever's 
ahead.  Have your second player blast aliens in their area, and 
your other player blast everything else.  If you're close 
enough, a nice SINGLE barrel shotgun blast will kill these 
guys.  Otherwise, go ahead and use the double barrel.  You 
should still have a few shells afterwards, and the mission is 
almost over anyway.

The next room is a teamwork puzzle.  This is the room with the 
elevator that Rosenberg is waiting for you in.  The first thing 
you should be doing is using the box with the two levers on 
each side.  One player hits one lever, and when the other side's 
lever comes up, the other players hit it.  Then they just take 
turns.  After a few pushes, aliens start to beam in.  Go ahead 
and take care of them, then go back to the levers.  You have to 
keep doing this until the elevator is all the way at the top, 
which will be signalled by some distant clanking and the levers 
will stop moving.  If you don't do this fast enough, alien 
slaves start to beam in, so try to take care of the headcrabs 
as soon as possible and get back to wailing the "use" key on 
those levers.  When they won't move anymore, climb the ladder 
right next to the lever box.  At the top of the ladder, walk 
on top of the elevator, and a small panel in the elevator's 
roof will open.  Drop down, there's Rosenberg, and he gives 
you a warning about the next room's security turrets.

This is the "use a Barney" test room from the training course.  
There are two turrets, one right by the elevator doors, and 
one right by the security panel doors.  Just lock onto them 
and start blazing away with the pistol or shotgun when they 
come down.  You shouldn't take too much damage from these.  
Don't worry about emptying the shotgun either.  There's a 
health charger when you're done with the turrets.  Afterwards, 
Rosenberg will run out to the retinal scanner, and you'll all 
go through the last double security doors--after blasting the 
zombie on the other side (as soon as the zombie's dead, 
Rosenberg will leap into your line of fire, BE CAREFUL NOT 
TO HIT HIM, this is the very end of the mission, stand in 
front of him if you have to).  After this, clear a path for 
him, and he'll run down to the train.  You don't have to 
activate the train or anything.  Mission complete.

--Three:  Surface Call
Briefing:  "To call for help, survivors need 
active communications.  Help Dr. Rosenberg 
establish an uplink with the outside world."

You start outside in the desert, where Dr. Rosenberg will slide 
open the gate for you to fit through one at a time.  He'll run 
across the sandy field to the Data Control door, but it's 
locked.  You'll have to go in the Satellite Operations door 
in order to get around to let Rosenberg through.  You can't 
just shoot the lock?  No.

Anyway, go in this door, and then through the small empty 
room to the next door.  In there is a large machine with a 
wheel on it, but you can't activate this yet.  You have to 
turn on the uplink computers first.  There's two ways you 
can go from here.  A long hallway, and a small storage room 
with some ammo clips (shotgun shells, 9mm, an armor battery).  
Go in there, bust open the little boxes and get whatever you 
need (remember to share!), and move on to the hallway leading 
to the giant room with the big crates all over.  As usual, 
enemies beam in--alien slaves.  Take them out, move down the 
ramp to the next area.  First thing you'll see, other than 
two more alien slaves, are a few bright blue barrels.  You 
can blow these up, but stand far away, because they'll kill 
you instantly if you're too close, and even if you're standing 
nearby, they'll probably do massive damage (I recommend the 
handgun).  Beyond the barrels are a bunch of headcrabs (about 
four) and a cart with some coal or dirt in it, and right behind 
that is a button.  If you try the button, you notice it doesn't 
work.  That's because the front wheels of the cart are blocked 
by a few planks of wood.  Smash these with the crowbar, and 
then hit the button.  The cart will move, smashing through some 
bright orange barrels (which explode, so stay away from them 
until they're clear--the other orange barrel still around can't 
be broken, and don't bother trying).

Keep moving and you get to a room with a conveyer belt, and 
more alien slaves.  There's also a couple wooden crates in 
here, which you can bust open with the crowbar.  One has 
shotgun shells, and the other crates have shotgun shells and 
a 9mm clip.  Work your way through a short winding hallway to 
get to a room flooded with radioactive liquid.  Stepping into 
this stuff is instant death, so be careful here.  Here's 
another teamwork puzzle.  Have one player get onto the cart 
(full of coal/dirt), and have the other player hit the button.  
It'll go to the right, which means it'll go under the dripping 
green radioactive stuff.  If you want, stay to the side of the 
cart and it shouldn't hit you.  Then jump off.  Next, have the 
player who stayed back hit the switch again so the cart comes 
back (yes, the same cart you just sent over, and MAKE SURE THE 
OTHER PLAYER IS OFF OF IT already).  There's a button on the 
far side where the cart-riding player is now, that controls a 
different cart.  Make sure the stay-behind player is ON TOP of 
the first cart (which again, should be right where it started 
off--in the middle of the room).  Have the first cart-rider hit 
the switch, sending the third cart forward, so when it reaches 
the stay-behind player, they leap from the first cart to the 
next.  Be careful, because the cart doesn't stop where you are, 
it keeps going.  And it goes under another leaking pipe.  
Again, stay to the right of the cart and you won't get hit.  
Now the last piece of the puzzle.  Once the second cart reaches 
the other side, there's a shallow cart with a little 
coal/dirt/stuff in it.  Hit the switch there, and the third 
cart will be sent all the way to the other side of the room.  
The player jumps in the shallow cart, and the other player 
hits the switch, and they're both safely on the other side.  
Keep in mind this note about the third cart:  the fact that 
it's short and shallow means that if you get in the cart and 
then move around in it while it's moving, you can potentially 
accidentally run right out, off the side of the cart and into 
the radioactive stuff.  Make sure you're FIRMLY in the cart, 
right in the middle, then stay still until the cart has come 
to a full and complete (as opposed to a full but partial) stop.

Move in the hallway, where there's another room with a handful 
of headcrabs along the ground.  There's also a crate in the 
corner here that you can bust open, and has a medkit.  Move to 
the next area, which is a long hallway, with alien slaves at 
the end.  Let them spot you, so they'll charge a shot and miss.  
Then go ahead and come out at them, Butch Cassidy and the 
Sundance Kid style, guns blazing.  The pistol is the best here 
since it's good at long range.  The next room has giant crates 
with a fork in the path, but there are alien slaves in both 
paths.  Take them out, and then you can split up if you want, 
since both paths lead around again to the center, where alien 
slaves beam in--right next to some bright blue barrels.  You 
can take out the aliens, or just aim at the barrels if you 
want, because the explosion will be big enough to blast all 
of them into chunks (just as long as, of course, you aren't in 
that area with them).  The safe distance is the room just 
outside of where the two paths meet.  From there, it's surface 

Watch out when you try to go up the steps, because there will 
be about three more alien slaves out there.  The third one will 
be pretty far away, but you should be able to take him out 
pretty easy with a locked-on Beretta volley of bullets.  From 
there, keep moving, into the swampy water path, and eventually 
you'll come to the rear dooway of the Data Control Operations 
building.  Find a door with an EXIT sign above it, and open it, 
you'll find Rosenberg waiting patiently on the other side.  
He'll come in, run up the stairs into a small control room, 
and tell you that someone has to go back down and align the 
dish.  Whoever has the most health should go, and the other 
player could stay behind.  They can go too, but once the dish 
is aligned, the other player could hit the button immediately.  
Head out the EXIT sign door--not the one YOU came in, but the 
one Rosenberg came in.  You should recognize the area, because 
once you get out there, it's a short walk to the little room 
with the wheel that you couldn't spin before.  However, getting 
there isn't going to exactly be a short walk.

Outside, a few alien slaves beam in, so make sure to get some 
good locks on them and blaze away.  If you're really low on 
ammo with that player, go ahead and fish the other player out 
of the control room to help.  Kill the slaves, go into the 
Satellite Operations door (it's a blue sign).  More slaves beam 
in!  Keep fighting to get to the control wheel, but another 
slave or two will beam in.  Make sure to take these guys out 
at all costs.  Once you do, go to the wheel, and HOLD DOWN the 
use key at it.  It'll keep spinning.  Another important note:  
KEEP AN EYE ON THE "UPLINK" LIGHT.  Once the wheel is in place, 
it'll turn green.  LET GO OF THE USE KEY.  Sorry, I don't mean 
to be pushy. :(!

Anyway, once that's set, back in the control room with Rosenberg, 
hit the button.  Rosenberg will run out to the radio room, test 
the uplink, and get a message.  He'll tell you a few things about 
your next mission and what you'll have to do.  Mission complete.  

--Four:  Resonance
Briefing:  "The rift between Earth and the 
alien world is widening.  Reset the dampening 
fields to prevent another cascade."

As you start, Dr. Keller tells you that you need to set some 
dampening locks and stuff.  He'll test a communications panel 
letting you know that he can radio you information right to 
your suits.  Then a door behind him opens, and it's time to get 
moving.  Notice in your weapons inventory, you'll now 
automatically have hand grenades.  They'll come in handy.  
Through the door, there's a busted up glass door.  Use the 
crowbar to smash the glass, then take out the zombies nearby.  
To the side of this hall, there's some red doors that lead to 
a room with a bunch of busted computer junk, and an armor 
charger.  But be careful here!  Once you use the armor charger 
even a little, two alien slaves beam right into the room, and 
there's a third slave that beams in right behind the closed red 
door in this room.  Blast them all, and move on.  Keep moving 
and you'll end up in a large, two-story plaza room, with a roof 
at the skylight.  Enemies start beaming in, slaves on the first 
and second stories.  You'll see helicopters far overhead, but 
don't worry about them.  It's the military moving in.  Which 
means you'll have to worry about it SOON, but later.

Keep moving, duck under the half-raised door, and into a glass 
window corridor, where there are alien slaves waiting for you, 
and others who will beam in.  Clear the place, move on.  The 
next room is a tricky little teamwork puzzle, that requires you 
to be split up again.  There's a small, half-broken vent behind 
a desk, with a lot of electrical current running through some 
liquid on the ground in front of it.  You can't just run through 
the electricity, because it will kill you.  But notice that when 
you hit the nearby button, a nearby door opens, the electricity 
is jammed by the door and stops.  Then the door closes soon, and 
the electricity starts up again.  What you have to do is have 
one player hit the switch then go stand in between the broken  
half of the door and the operational door.  The door will shut 
on the player partially, then reopen.  This way, the electricity 
stays as long as the player stays in the door's path.  Let the 
other player crawl through the vent (preferably the one with the 
most health, since they gotta fight a few monsters here and 
there), and then have them keep moving.  Jump up some rocks and 
then you'll be in another office type room.  You'll be on a 
higher ledge, where the door next to you is locked.  Once you 
fall down to the lower levels (it's not far enough to take 
damage, but you can land on a table if you want to), an alien 
grunt will beam in on the upper level.  For a little handy 
damage, leave a grenade on the floor on the upper level before 
jumping off.  Otherwise you can just chuck a few grenades up 
there when he beams in.  Either way, use a couple grenades.  
Try to only use a couple, you still want to have a few left, 
and you only get five to start with.  Make sure you don't bounce 
the grenades off the wall or the railing.  Just stand right 
against the upper-ledge's wall, point straight up, and then angle 
down a little bit and toss a grenade, it should land very nicely, 
and blow away the grunt.  But the VERY SECOND this grunt is 
beaming in, another alien grunt beams in where your other player 
is left behind.  Make sure they're ready, and paying attention 
(the grunt beams in by the intact but locked double glass doors).

Have your scout player take a little armor from the charger on 
the wall in that room (save some for the other player if 
necessary), then move out, and blast the alien slaves around 
the area.  There's a security room in the middle of the 
circular corridor that you'll be in.  You get in there, there's 
more shotguns, the Magnum(!) and a security override switch 
that will open the glass double doors for your other player to 
finally join you again.  Stock up, share health and armor and 
ammo, then move on to section with the flight of stairs and a 
health charger.  Go up the stairs, kill the grunt, 
(==bonus note:  at the top of these stairs, directly through 
the doorway, turn left and you'll see a vent, break this open, 
and use stacking to get into it--which means one player ducks 
and the other player jumps on their heads and duck-jumps into 
the vent--for some free goodies==) and move on to the lab room 
with the overturned tables and stuff.  There's an alien grunt 
to the right, and an alien slave to the left.  Clear them out, 
use the health charger if necessary.  There's a double glass 
door that opens with a button press, but this is the area that 
your scout earlier came out of.  It's that upper ledge room.  
Never mind this place.  Keep moving, past that room, past the 
door with the EMERGENCY AUTO LOCK sign in big red text next to 
it (if you move into this door, Keller will tell you that he 
needs the dampening locks thing done first).  At the end of that 
hall is some short stairs, with headcrabs at the top (blast 
them).  Up a few more stairs, another alien grunt, and then 
from there is a giant room with giant rusty pipes in them (more 
like tunnels than pipes, but you can't go in these, so).  There's 
a small staircase/catwalk that goes over one pipe, and on that 
other side is another alien grunt.  Once you're on this side, 
you'll notice there's a ladder on either side.  You have to go 
up this second ladder here, not the one on the side with the 
door you came in.

Have both players go up the ladder, and there's a circle wheel.  
Here's a challange.  One player has to HOLD DOWN THE USE KEY to 
keep turning this wheel, for quite a while, as aliens beam in 
behind the player.  Make sure the other player has either more 
ammo or is a better aim.  The player turning the wheel should 
have more health though, since they might take damage.  You can 
break off your wheel turning to help attack, but the longer you 
hold off turning the wheel ALL THE WAY, the more enemies beam 
in.  Eventually, tougher enemies come in, first headcrabs, then 
slaves, then an alien grunt!  You want to be done before the 
grunt shows up.  When the wheel is done, it'll stop moving, and 
the little beacon thing above the pipes (which is above the 
wheel) will start blinking and sucking in energy or something.  
And the enemies won't beam in anymore, so do this quick.  
(Mini-note:  if you complete turning the wheel without stopping, 
the beacon thing will close when it's done.  Otherwise, it'll 
stay open.  It doesn't matter, because when it's done, it's done, 
and it's time to move on.)

Now go back down the ladder.  Go across the catwalk to the 
other ladder.  Notice that this area is larger, so there's 
more space for enemies to beam in.  Again, same tactic.  Have 
one player turn the wheel until it stops, and then the other 
player should cover the wheel-turning player.  If you're 
playing in one-player mode, you can turn the wheel while the 
conputer controlled player can cover you.  Just make sure they 
aren't too far in harm's way, or they'll die while you're 
standing there like a dork with a wheel in your hand and 5 
aliens behind your back.

Now, leave the room, go back down the small stairs (it's the 
first stairs you'll come to anyway) and go back to the 
previously locked EMERGENCY AUTO LOCK door.  It'll be open 
already, with an alien slave waiting for you.  Blast it, 
move through, you'll see to your left a couple little windows 
down to the area where you started in, where Keller is.  
DON'T jump through these windows, just keep going down the hall.  
Your first right will be an alien grunt waiting in a dark 
corner.  Blast him, and then keep moving, ducking under a 
half-lowered door, and you'll find a familiar spot.  It's the 
SECOND story area of the plaza room.  Alien slaves beam in, 
and an alien grunt will beam in on the roof.  If you want you 
can take out the grunt, or just wait since you're going to 
the roof next anyway.  But when you get there, two more grunts 
will beam in.  Probably best to try to take out the grunt 
now--go with the Magnum.  Here's a tough part.  When you get 
up to the roof, there will be two grunts waiting for you.  
One on the roof level, and one on an upper ledge.  Make sure 
to LOOK UP here so you can spot this other grunt, because you 
may run around getting hit without knowing where he is.  
There's a vent lit by a red light here.  Blast it open, then 
the place will shake as MORE alien grunts beam in.  This is 
the part where my brother and I were in a frenzy.  Make sure 
you have Beretta or Magnum ammo for the alien grunts on the 
ledge, and then take a close range shotgun blast or three to 
the alien grunts in front of you.  Don't get too close, or 
they'll start beating you with their giant arms, which can 
actually throw you way off balance.  A few well thrown 
grenades help.

When the place is clear, go into the vent (duck-jump) and make 
your way to the end of the vent, which is a bottom opening that 
you have to bash through.  You'll be in a control room with a 
button, a health charger, and a door (oh yeah, and a headcrab).  
Also, a nice view of the outside area.  Dr. Keller will send 
you a message telling you that there's a weak spot in the 
conduit out there, so you should keep an eye out when you're 
turning another dampener lock wheel.  This is similar to the 
previous wheel turning, but only in the fact that you have to 
protect someone from turning the wheel.  

There are a few things you should do before slamming on 
buttons and going through doors.  There's a small panel on a 
wall by the health charger, that acts as a button.  It's not 
on the computer control panels in the middle of the room, it's 
ON the wall.  Hit it, and a little wall panel will slide open, 
with item packs.  They're close together, but they're set up 
so only one character can get one pack.  Make sure both 
characters get a pack before you set out.  They'll fill you 
up with a bunch of ammo, armor, goodies.  Very necessary.  Now, 
after you charge up on health (with the health charger--if 
necessary at all), one player has to go out to the "DISP. FIELD 
DAMPENING LOCKS" door.  The other player hits the main 
button in the room, which closes the internal door and opens 
the external door which leads to a catwalk, which is where 
your wheel is.  Before you start jamming on the wheel, though, 
you might want to pause and take a break.  For like a minute, 
maybe two.  Ever play Goldeneye for the N64?  Remember when 
you had to protect Natasha at the keyboard while enemies busted 
windows all around you, blazing gunfire all around, possibly 
hitting her or you or the computers?  This is worse.  Imagine 
that the enemies beam in out of thin air, and are constantly 

Okay, I'm ratcheting up the tension here, but as long as you 
keep a cool head, and a solid trigger finger, you should make 
it through this pretty easily.  Once the task-player starts 
turning the wheel, there's a large green crack in one of the 
giant pipes, overhead.  Sparks shooting out and stuff.  Then 
the dreaded Alien Controllers beam in.  These are flying guys 
that rapid fire energy balls.  Now you don't have to worry a 
whole lot about some of these things hitting you, since 
they'll mostly take away armor at first.  But once you're out 
of armor, you better be done or taking cover.  Your pal in the 
control room better be doing their best to blast these things 
out of the sky, with either the Magnum or Beretta (START with 
the Magnum, since it's high powered).  Once the wheel stops 
turning, have the task-player, out on the catwalk with almost 
NO cover, run back to the door.  It won't open, so if the 
stay-behind player in the control room hits the button, 
nothing will happen.  Now the objective is JUST SURVIVAL.  
Keep shooting the controllers out of the sky.  The best 
place for cover, for your wheel-turner, is in that small 
hallway with the door.  You have less room to dodge, but 
the controllers will have a small window they'll have to be 
in to shoot at you, and from that view you should be able 
to hit them first.  Keep trying to move around, but the key 
really is to SHOOT THEM FIRST.  If they get in too many 
shots (or the "big ball" energy shot), you're toast crumbs.  
Non-stop fire is the key.  Usually, a single Magnum bullet 
will take down a controller.  Once you're out, if you're 
daring, dash back out to the catwalk, lock onto a controller, 
and try blasting them with shotgun shells.  If they're nearby 
the catwalk's turn, you can do some nice damage to them, but 
make sure to backpedal back to cover.

Eventually, after a few panicked radio transmissions from 
Keller, and a LOT of dead controllers smack to the ground, 
the damaged pipe outside will glow bright green, spraying 
white energy fragments all over (this really ISN'T as phallic 
as it might sound).  Then everything will stop, and Keller 
will send you a message.  You may not be able to hear it over 
your sigh, or your panic attack.

Okay, I admit it, this was actually easy the second time 
around now that I knew what to do.  Especially since I went 
into the battle FULLY stocked up (as opposed to when Josh 
and I played together, we were running around screaming in fear 
as our health dropped dangerously low).  But still, keep on 
your toes, people.  You WILL run out of Magnum bullets before 
the controllers stop zapping in.

Anyway, Keller mentions sending a tram to you on the nearby 
rail.  Screen fades as usual.  Mission complete.  Now is a good 
time to towel yourself off.

--Five:  Domestic Violence
Briefing:  "A satellite controls major recovery 
systems.  Locate a security guard who knows 
the satellite signal codes."

You start with Keller in a tram, and he tells you that you 
need to find a guard with some access code.  Wait for the 
tram door to open, both players move out, Keller tells you 
he'll see you in some other location, so forget about him for 
now, the tram will depart.  There's a window in front of you 
with two smash marks on it.  Break the window, go in, hit the 
control panel.  Go BACK out the window and the verticle 
double doors will be open.  Put both players in the room so 
they'll both be scanned by the security "thingy."  Move on 
to the lobby.  There's a small room with a window that you 
can bash through and stock up on ammo.  Go ahead and follow 
the red-striped "elevator" path because it's just a dead end 
with a non-functional elevator, and a dead Barney and sci.  
There's a pistol there for a nice clip of 9mm.  Now finally 
you can go down the "dormatories" and "aquatic center" path.

And don't worry about the VOX computer announcment system, it 
just gives general announcements, and you don't have to pay 
attention to it.  Even when it says there's an intruder 
detected on level 3, which is where you are(!!!!!!!).  Anyway, 
the end of your next hallway is a busted up window with 
another security guard and a button.  Hit the button, go 
through the glass doors (they close fast, so you may have to 
hit the button quick), and you'll be in the dormatories 
hallways.  This path forks, and both paths are short, with 
aliens down both halls.  Note the nice carpeting on the floors.  
Very tasteful!  Oh yeah, and none of the doors work for now.  
You can try them yourself if you want, after you kill the 
aliens.  Once you start moving down these halls, MORE aliens 
beam in all over, and it becomes a total mosh pit of alien 
slaves.  These guys are weak so just keep blasting away.  In 
the center of where these paths meet is a small lounge with 
two soda/pop machines (push a button and when the can comes 
down, you automatically pick it up for 1 health point).  
There's also a health charger, for the impatient.

Keep moving and at the END where the halls meet is a small 
staircase up, and a right turn.  Be careful here.  There's 
a sentry gun AND a tripmine.  Just chuck a grenade or two 
around this corner to clear them and they should be no problem.  
Keep moving up a stairwell, and into the pool room.  Read the 
pool rules--NO NUDITY, PEOPLE.  You need your HEV for protection 
purposes, after all.  Anyway, check the stairs and you'll find a 
health kit and armor battery.  And then notice a vent lit by red 
light in the far corner.  This is where you have to go.  Break 
the vent, and stack to get up there.  Again, this means one 
person has to duck, the other person jumps on their head and 
then duck-jumps through the vent.  So one person, again, has 
to stay behind.

For your go-ahead scout/pointman person:  once you kill a 
headcrab in the vent, aliens will beam in, in the pool room.  
If you want, you can just go back out the vent and blast the 
alien slaves.  Then stack back into the vent.  From here, keep 
moving and you'll end up falling down into the locker room.  
There's a big gate sort of door that leads back out to the pool 
room, which is how you join up again.  That wasn't so long.  
Anyway, go back into the locker room and you'll find some stuff 
lying around.  There's ONE locker in here that opens, with 
grenades and shotgun shells inside (this locker is near a 
ladder leading up).  Apparently someone felt they needed 
protection while swimming.  Anyway, go up the ladder in this 
locker room (you COULD throw a grenade up here first if you 
want, just to be safe).  Keep moving through the vents, and 
you'll find an area where you can overhear a human grunt 
talking about not being able to find targets or something.  
QUICKLY jump past these vents (don't worry about going down 
the vents, just jump back out and keep moving forward) and 
then blast through the cracked, reddish vent wall AHEAD of you.  
Inside are snarks.  Blasting the broken wall open will cause the 
grunts to discover you, but if you bust one of the below vents, 
you can drop the snarks down there and they'll completely go 
crazy on the grunts.  Stay up there until the grunts or snarks 
are dead, then go down and mop up.  WARNING:  if you go down 
while snarks are still alive, they'll attack you.  One grenade 
should clear the area pretty well, if you feel like using a 

Keep moving and you'll end up in another forking (as in a 
pathway that forks, people) dormatory hallway with a lounge 
in the middle.  Human grunts are here, blast them.  You'll be 
able to pick up an M4 here or there from the dead grunts.  In 
the lounge, there's a Magnum with bullets.  After you clear 
them, notice that ONE dorm room is open, with some ammo and 
armor in there.  It's Gordon Freeman's room.  Neat.  Anyway, 
keep moving and you'll find yet another tripmine and sentry 
gun.  Grenade them.  These WON'T be around a turn, they'll be 
right in the path, so make sure to be careful walking up here.  
If you don't see anything, you're probably going backwards.  
Keep moving and you'll end up in what looks like the place you 
STARTED, but it's not, it's just the north wing, where Keller 
has been waiting for you.  To get to him first, you have to 
crawl through a couple windows, going through a security room 
(there's a computer panel with a keyboard here, push the 
keyboard and the screen will turn blue, opening the doors).  
You'll move to the end of the tram where Keller is, and he'll 
tell you that he's glad to see you, BUT you need a security 
guard with the access codes.  Oh yeah, DON'T run too rampant 
here, because you can run right up the sides of the benches 
here, and if you jump over the sides, you'll probably fall off 
to your death.  Just go back, and you'll see a green stripe 
with "LIBRARY" on the wall.  Follow this--you could also go to 
the red stripe ELEVATOR area, but it's just two grunts waiting 
for you inside (watch for them throwing grenades at you) and 
you can't use the elevator.  Move to the library, which is up a 
flight of stairs, and at the top is two more sentry guns.  Keep 
going and you'll end up in a big room with a lot of books.  
THIS MUST BE THE LIBRARY, I THINK.  The library is first on the 
right, but at the end of this hall, on the left, is a small room 
with a PERFECTLY LIVING security guard.  He won't move until the 
grunts are cleared out of the library.  Make sure the grunts don't 
come and kill this guy or throw grenades at him, because then 
you're really screwed.  Just plow into the library and start 
slicing up the grunts with grenades, shotgun blasts, or assault 
rifle fire.  There are doors on the upper level of the library 
that open with MORE grunts, so SCOUR THE ENTIRE AREA for grunts, 
until you're really sure that no little corner has one last 
grunt hiding.  Then it's time to go to the security guard.  He'll 
know when the grunts are gone.  You don't even need to "use" him 
to get him to follow you, he'll just start running down the path 
to the tram.  At this point, STAY BEHIND THE GUARD.  You don't 
want to block him, and you don't want to accidentally leap off 
the edge of the tram catwalks to a black death.

Once the guard gets there, that's it.  Mission complete.

--Six:  Code Green
Briefing:  "A satellite must be in orbit for 
recovery systems to operate.  Upload the 
satellite signal codes before the delivery 
rocket launches."

You start in a room where you have to listen to Keller telling 
you what it's time to do in this mission.  A power-lock door 
(there's a red light next to it connected to the door itself) 
will open when he's finished, and you move ahead to some room 
with crates.  There's batteries and ammo in here, and then from 
here is a flight of stairs.  You'll hear gunshots.  There's a 
Barney around a corner fighting human grunts, but your path is 
blocked by a cracked desk.  Go ahead and blast through the desk 
if you want (this is what I did) and then move in and open fire 
on the grunts.  Don't worry if the Barney dies--it won't fail 
the mission if he does.  In this room, after the grunts are 
dead, there's only one door that will open, but it only opens a 
tiny bit, letting you know it's blocked from the other side.  
From here, you have to go BACK to the vent next to the locked 
power-lock door (noted by the red light of course).  You don't 
have to stack to get into this vent, actually, you just break 
the vent cover and then DUCK-JUMP into it (either hold down the 
jump button, where you'll automatically duck at the top of your 
jump, or jump, and at the top of your jump hit the duck button).  
This leads to the roof of an elevator, which is stuck.  From 
here, you go UP a pretty obvious ladder, through a long vent, 
and then there's a couple spots where you can look down.  The 
second spot is a poor Barney pleading for his life--and he gets 
shotgun blasted (out of view, though).  The other paths are a 
dead end, but what you're supposed to do is NOTICE that there's a 
door blocked  Blast the crates below, and then go BACK to the 
elevator roof, where you'll have to stack to let ONLY ONE player 
up into the vent where they can go all the way back to the 
Barney-vs.-grunts rooms, where the previously blocked door will 
open.  Remember:  you don't have to go down ANY stairwell to get 
back to this room, it should be on the second story where you'll 
come out of the vent (next to the still locked power-lock door).

In the previously-blocked door is a grunt you have to take out, and 
a lever under a security override sign.  Hit it, and the 
power-lock double doors outside this area will be unlocked (note 
the green light).  Open these doors and you'll see an elevator in 
front of you.  Feeling suspicious?  You should be.  Directly to 
SIGHT.  Throw a grenade in there and he'll panic.  He may not die, 
but it's the distraction you need.  After your grenade goes off, 
run in there and start blasting.  Remember, it's only you by 
yourself--your stay-behind guy will still be in the elevator 
(unless they could get out some way that I haven't figured out, 
but I doubt this because we really tried).

Anyway, FINALLY, in here, hit the button next to the elevator 
door.  It opens, and you'll finally be reunited.  On one end of 
this room is a couple ammo boxes (one for each of you) that 
will totally fill your 9mm ammo.  On the other end of this room 
is a soda/pop machine.  Facing the machine is a doorway leading 
right outside.  If you even peak out this door, THREE human 
grunts will start coming in after you.  Be ready for them, and go
 ahead and saw into all of them with your M4.  To the left from 
this door is a small broken ledge, where you can fall safely down 
to some crates.  The crate on the very top will break with 
Magnum bullets in here.  You'll definitely need bullets, because 
you'll be in a huge, outdoors, closed off area with four grunts 
already there, and more who constantly chopper in.  If you can do 
this quick:  FROM WHERE YOU FALL down to the crates, you head to 
your RIGHT, there's two grunts, use contact grenades if you have 
them (make sure not to be aiming down at all, but dead ahead when 
you fire these things).  Then all the way at the end, to the left, 
is a little dead end with two more grunts, and some health, armor, 
and ammo.  Another contact grenade should blast these guys into 
chunks while you and your friend can snatch up all the health and 
ammo.  From here, you have two options.  Directly on the opposite 
side of the dead-end (i.e. to the right of the main road you came 
to this dead-end on) is a small pathway that you can go in and 
take cover.  The giant OSPREY HELICOPTER will be out there, 
constantly dropping in more troops.  So you can either keep moving 
and spare yourself from these guys, or, if you are one hardcore 
gamer (like my brother and I), you can take down the giant Osprey.

Here's how we destroyed the Osprey.  First, there's two rotors, 
one on THE END of each wing.  Use your M4 or Magnum to hit these.  
YOU CAN'T lock on to the Osprey because it'll only let you shoot 
the center.  You have to do this with free aim.  Keep pouring fire 
onto one rotor at a time.  When the Osprey stops in the middle of 
the road there, two grunts will rappel to the ground.  Go ahead 
and move your fire to these grunts, so you can take them down 
(switch to the shotgun real fast for this, if you can), so you can 
pick up more M4 ammo from them.  The mission is almost over, so 
don't worry about running out of M4 ammo as long as you don't take 
too much damage and still have Magnum or shotgun ammo left 
(otherwise--just run).  Anyway, when a rotor takes damage, black 
smoke comes out, and then stops when it doesn't take fire.  
Eventually, the rotor takes ENOUGH damage and it will CONSTANTLY 
pour black smoke.  This means:  aim at the SECOND rotor, and 
keep hitting it.  When it's taken enough damage, the entire Osprey 
will come down.  There's just one last thing to note here:  when 
it comes down, it'll keep flying in whatever direction it was 
heading.  And when it hits the ground, it'll blow BIG.  If you're 
under this, you'll die.  You can use the crates, dead-ends, or 
the doorway to take cover once the Osprey is done.  If you 
survive this, pat yourself on the back.  And possibly take a 
little pause break.  Wash your sweaty hands or something.  Get 
a nice drink of water.  The mission is almost finished.

From here, the room has a few crates but only with a couple 
healthkits.  Up the stairwell here is more rooms with SEVERAL 
grunts.  Toss some grenades in doorways, or just come in blasting 
with Magnum, M4, and shotgun fire.  After they're cleared, there's 
a security room with a window that you can't break.  Don't 
worry, there's a door nearby with at "SECURITY" sign on it which 
is how you get in this room.  In here is a button that will 
open another power-lock door, that's right outside of the 
security room.  In here is a computer room with a few readouts, 
and in a corner is a panel with a button.  When you hit it, it 
doesn't work and Keller tells you that the traffic control has 
to be online (or... something, you know).  All this really means 
is that one player has to go back to the security room and hit 
the button again, while the other player stays by the 
non-functional button.  Security-room-player hits button, and 
the other player hits the other button.  Keller will tell you 
that it works:  mission complete.  Give your M4 a rest.

--Seven:  Crossfire
Briefing:  "Prototype equipment must be used 
to seal the dimensional rift.  Manually raise 
the displacement beacon into place."

You start in the backbone of most FPS games:  a sewer level.  
There's a couple release valves here that open doors.  You don't 
have to hold these down, just hit them once.  After a couple, 
there's a giant maze like room with grunts EVERYWHERE.  Be 
careful here, there's even a couple grunts in a little 
green-lit tunnel.  And there's a lot on the upper catwalks, 
and they run around a lot.  It's up to you how well you'll do 
this scene.

From here, another hallway with a grunt--AND THEN ALIENS!  Aliens 
start beaming in.  Yes, the human grunts should still be attacking 
the alien slaves when they show up, so you might be able to let 
them fight it out.  But the human grunts will probably win easy, 
and then come after you.  There's a few ahead in an area with 
two stories.  You're on the lower story, on a cement floor, with 
a view of the above catwalks.  Keep moving and clearing, and 
you'll come through a doorway into a hallway, where to your right, 
up a ramp, is a grunt behind some sandbags, and then in front of 
you will be a doorway, with a detatched door next to it.  Take out 
the grunt, and move in here, where there's an alien slave you 
have to blast.  After the threats are gone, you'll notice in 
this generator room is a cracked wall, and an explosive barrel.  
DO NOT!!! shoot the barrel immediately.  Destroy the wooden crate 
NEXT TO the barrel, then get behind the barrel and push it 
AGAINST the cracked wall.  Then move out of the room, throw a 
grenade through the doorway at the barrel.    It'll explode, and 
a nice hidden room with a TON of ammo and a health charger will 
be open to you.  There's another little section like this, so the 
next time you see an explosive barrel, DON'T shoot it just yet.

Anyway, up the ramp you'll be on the second level of catwalks.  
Alien slaves beam in, one on the level you're on, and one on the 
ground BELOW you.  Blast them, and move on through a small hallway 
to MORE catwalks, where there's lots of grunts waiting for you.  
Move in and open massive amounts of fire onto their soft faces 
and skulls.  By the way, I think this is the first Playstation 2 
game where someone says "SHIT."  The grunts, that is.  Getting 
back to the walkthrough:  after this area, you keep moving to 
ANOTHER room with catwalks where there's a grunt on an upper 
catwalk and the lower catwalk in front of you (taking cover behind 
a military crate).  When they do this, TWO alien slaves will also 
beam in, on the catwalks behind you.  You can take cover from one 
at a time, and since the grunts are pretty far and don't have the 
best opportunity to hit you, try to take out the slaves first 
(duck behind crates or run back behind walls whenever necessary, 
the shotgun is a good choice here), then focus some Magnum blasts 
on the grunts.  There's an explosive barrel on the upper catwalk 
here, DON'T destroy it (if you can at least, if it's destroyed 
then never mind it anyway).  When you clear the place, go up 
another ramp ahead, and on the upper level will be the explosive barrel.  
You aren't safe yet, though.  Alien slaves beam in, one 
next to the barrel.  Take him out with the Magnum.  Get the other 
one, and then you're safe to move the barrel.  Notice there's 
a generator behind a fence, and the fence has a crack in it.  
Behind the cracked fence is three armor batteries.  Pretty obvious 
what to do here, move the barrel up to the fence and then get back 
and shoot it.  Nice big armor bonus.  Moving on.

From here there's a room where there's a couple grunts across a 
large catwalk floor covering giant pipes below.  There are 
suspicious looking things on the catwalk floor--DETPACKS.  Stay 
back from these, they immediately explode and take out the floor.  
They also crack a couple of the pipes.  STAY AWAY FROM THE STEAM, 
it will kill you instantly.  Move down these pipes carefully and 
there will be a wheel.  You have to HOLD DOWN the use button on 
this wheel, and once the steam stops, keep holding it down, because 
if you let go, the steam comes back on (remember, instant kill 
steam).  Have the other player run up there, where there's 
ANOTHER wheel.  You don't have to hold down use on this, but it 
doesn't really matter.  It'll turn, and after a couple seconds, 
the pressure generator there will shut down, and both cracked 
steam vents will shut off.  Now you can go through the door down 
there that was blocked by steam--the only thing in this are some 
health kits, 9mm, and contact grenades.  Don't worry about the 
steam turning back on at this point, either.  Anyway, both of you 
can head up the ladder to the door.  There's three grunts in this 
room, and a radio you can destroy.  There's another catwalk room 
in here with alien slaves.  From here is another room with some 
more grunts, another explosive barrel (I don't think this one 
does anything, I tried using it to blow up the SURFACE ACCESS 
door and it doesn't work), and more items.

There's a door with a "SURFACE ACCESS" sign, and some blue 
barrels behind the door.  The door doesn't open, and you can't 
blow up the barrels from here.  Keep moving through the other 
door.  You'll find the giant displacement beacon, which is on 
a platform.  Have one player stay on the platform with the beacon, 
and the other player hit the controls (a little "up arrow" button) 
to raise the beacon.  When one player raises the beacon, alien 
slaves beam in.  When you clear them, the beacon stops because 
the doors are jammed and won't open to let the beacon through to 
the surface.  Keller tells you to find the obstruction and get 
it cleared.  Look around to one of the double doors, one doesn't 
open all the way.  Notice there's some broken pipes and stuff 
hanging down.  One player should still be up on the platform 
with the beacon.  Have that player jump onto the catwalk with 
railing, and then at the end of that catwalk (the end with the 
door that doesn't open) there's a large pipe that you can jump 
to.  At the end of that pipe is another pipe and so on until 
you're across the room, to the broken giant surface hatch door 
(thing).  Crawl up here, through some hanging wire thing (it 
won't do any damage so don't worry) and you'll find a wheel to 
turn.  Just hit the wheel, it turns, and MAKE SURE to have your 
player on the lower level STAND CLEAR of the controls.  In fact, 
just get away from them.

Now go down through the broken hole in the floor where the 
controls WERE (I'll let you see for yourself what happens of 
course), and you'll find another area with the manual controls.  
That means a box thing with a lever on each side.  Have one 
player hit one lever, and when that goes down, the other goes 
up, and the other player hits that.  This is just like the 
earlier level where you had to manually raise the elevator.  
After enough times, the beacon is fully raised to surface 
level.  Mission complete.

--Eight:  Intensity
Briefing:  "The prototype equipment requires 
huge amounts of energy.  Activate the beam 
matrix to power the displacement beacon."

This mission is a cakewalk except for one giant puzzle at the 
end, where you have to go through a lot of crazy stuff to 
activate the beam matrix.

You start with Keller giving you another briefing, and a 
nearby scientist working away at a keyboard.  From here it's 
just a bunch of winding rooms through some weird experiment 
labs where alien slaves, grunts, and houndeyes beaming in, with 
the usual frantic sweet Half-Lifeian action.  Go ahead and take 
your time, you'll eventually come to the beam matrix controls.  
The rest of this level, other than the beam matrix areas, are 
no problem at all to figure out except for one small area where 
there are slave-like green electric beams shooting out of a 
room.  All you have to do is smash the window, and push aside 
the dead scientist, and hit the button.  This should turn off 
the slave collars.  Weird place here.

There's a room with a big "SECURITY OVERRIDE" button on a 
control panel, and across from that is a small room with glass 
windows.  In this room are three colored beams, blue, red, and 
yellow.  The primary colors.  You can see through a bulletproof 
window in this room an area where the beams combine and travel 
through.  There are several tricky parts about this area.  You 
CAN'T hit the SECURITY OVERRIDE button until ALL of the three 
beams are turned off, and you can't turn the beams on without 
the security override being turned off.  Outside the door that 
the security override opens is an elevator, but Dr. Keller will 
tell you that he can't activate the elevator until the beam 
matrix is activated.

To activate the beam matrix, ONE player has to go through the 
security override door, and the other player has to stay back 
with the beam controls.  The player who went through the security 
door will be referred to as "the scout" and the stay-behind will 
be the "beam controller."  Now, have your scout run down through 
the door to the left, and they'll be in a room with some fences 
that provide a view below, where there are THREE large crystals, 
and some winding little maze area.  There's a ladder that leads 
down here, and this is where the scout has to go.  Make sure your 
beam controller isn't doing anything yet (except deactivating 
the security override).

What you have to do is match up each large crystal with a 
combination of beam colors to activate them.  To do this, 
you have to combine two colors of beams while guiding them beam 
by using the buttons on the lower levels (where the large crystals 
are) by lowering and raising reflective plates.  Keep in mind 
that when you're turning on the beams, you DON'T want your other 
player down there where the beams are shooting through.  This 
is all you have to do for this puzzle, just make sure the 
three crystals get hit with their right colors.  Some quick 
trial and error.  This puzzle is EXTREMELY easy once you know 
what you're supposed to do to solve it.  After all the crystals 
are on (they'll be glowing and charged with power), you raise 
ALL of the mirrors, and then activate ALL THREE beams, and the 
beam matrix will be activated.  Things start exploding and 
alarms go off, Keller tells you that the beam matrix is on, and 
then aliens start beaming in ALL OVER.  Now you can't turn off 
the beams, so your beam controller has to go BACKWARDS through 
the whole level (it's the only way you can go that isn't locked, 
from the beam control room), while your scout has to go forwards 
to meet them.  Your beam controller can't go ALL the way back 
because there's a retinal scanner that only works on one side, 
and your scout has to activate that to let your beam controller 
all the way back to the elevator.  This entire time, aliens are 
still beaming in, including slaves and alien grunts.  Blaze 
through these the best you can without losing much health, and 
make it back to the elevator.  It goes up, keep moving ahead and 
you'll end up back in the room with Dr. Keller.

Mission complete.

--Nine:  Rift
Briefing:  "A resonance reversal may seal the 
dimensional rift and save the planet.  Use the 
displacement beacon to initiate a reversal."

Last mission.  As per the natural balance of good games, this 
level is pretty straightforward, as opposed to the previous 
mission.  Your job here is to protect the displacement beacon as 
Keller activates it, while also activating the crystals.

When you start, Keller's talking to you about blah blah blah and 
all that.  There will be two doors open, one for each player, with 
a giant stock of ammo, AND the Rocket Propelled Grenade Launcher.  
You want to save all the rockets for the boss in this one.  
Anyway, you'll keep moving, but there's no fighting yet.

You'll get outside to where all the chaos will be.  Just a giant 
rock-wall-surrounded arena.  Keller tells you that he'll need you 
to activate a few crystals, and you'll have to defend the beacon.  
It starts easy, so don't sweat.  You can sweat when you're 
fighting off endless hoards of invincible enemies that kill you 
in one hit!  Or actually not.  Alien slaves and alien grunts zap 
in occasionally, as Keller charges up the displacement beacon.  
There are three switches around the beacon, they activate the 
crystals.  You can activate the first one soon, and you won't 
have to fight any monsters yet.  Then Keller will start charging 
again.  Listen for his cue, when he gets to 100%, he'll tell you 
to activate the next crystal NOW, and then find a switch you 
haven't hit (one WITHOUT a big glowing crystal above the switch), 
and activate it.  I think you have to hit them in a certain order.  
Counter-clockwise I believe (the area you start in being the bottom 
of the clock).  This really isn't the hard part.

The hard part is a big swarm of enemies.  If you're only playing 
on one-player mode, you should probably leave the other player up 
on the ledge where they can get a good shot.  You just stay down 
there and hit the switches when it's time.

There's also a small double-door armory down there, but it doesn't 
open until the third switch is hit.  This should be AFTER the 
alien boss/bird thing flies in.  It stays in the air and it will 
fly behind the walls now and again.  You want to keep it from 
destroying the beacon, so this is where you use the rocket 
launcher.  Get a good lock on, fire a rocket (or two), and then 
lock off because there will still be grunts beaming in.  And you 
can't shoot the grunts in their reflective armor areas, only in 
the "dark meat" areas.  It's easy to just blast away the front of 
their torso, but try to get them quick, since their attack hornets 
will zoom around rocks, or other cover, to hit you.  The alien 
slaves can be shot anywhere on their bodies, but if you can't take 
them out immediately, make sure you take cover behind something.

Keep shooting the alien "hovership" with rockets, and if/when you 
run out, go ahead and open fire with the Magnum, or the M4 
(remember that the armory should be opened nearby at this time, 
so grab all the rockets you can).  Anything, as long as you 
keep shooting it.  It'll crash soon, and make sure to stay out 
of its way.  This thing takes a lot of hits, but there's no 
trick to beating it, other than sustained fire.  After this, clear 
the rest of the enemies from the area.  Then the ending just 
plays out.

I notice there's space for another mission after this, but I 
haven't gotten it yet.  If anyone can e-mail me about it that 
would be great (I suspect I have to get at least a B or an A 
rating on each mission for both players before I can open the 
next one).

After this mission, though, a credit sequence should play.  Go 
ahead and celebrate.  Get a pizza, rent a movie.  Or just have 
a cigarette.  It's a good feeling.

--Ten:  Bonus alien slave mission

It's been verified by about 20 people that to get this mission, you have 
to get an A rating on each Decay level, with BOTH characters.  There's a 
lot of enemies to kill and stuff to do but it's still a short level 
(about as short as the others I guess).

The most detail came from "Christopher Beer."  He tells of grunts and 
explosive traps, and some button pressing.  Shouldn't be too hard if 
you've worked through Decay already and gotten the A ratings.  He also 
mentions that if you push select in Decay, you can see your current 
stats (kills, accuracy, damage).

Oh yeah, and the alien slave's health meters are the green strip along 
the bottom.


3.  Credits

Half-Life copyright Valve LLC. 1998/2001

Walkthrough written by:
Josh and John Cable

Walkthrough copyright 2001, Josh and John Cable

Contact us:

AIM:  Jhoh Cable

"First grunts beam in--AND THEN ALIENS!!!!!!!!  AAAAAAAAAAAAAAAA OH MY 
GOD MY ENTIRE HEAD IS ON FIRE!!!!!!!!!!!!!!!!!!"

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