Does anyone know the odds of finding a blue chest per floor?

That depends of the number of chests per floor. Since the chance that a random chest turns out to be blue is 1.953125%, the chances to find at least one Blue Treasure per floor with different amounts of chests looks like this:

1 Chest: 1.95%

2 Chests: 3.87%

3 Chests: 5.75%

4 Chests: 7.57%

5 Chests: 9.39%

6 Chests: 11.16%

7 Chests: 12.90%

8 Chests: 14.60%

9 Chests: 16.27%

10 Chests: 17.90%

With an average of 4 chests per floor, the total expected number of Blue Chests is 7.65625

So does that mean that you know how Red Chests are filled?

Only what type of item the chest contains. I've never looked at the actual (possible) content per floor though, which seems a lot more complex.

How do Red Chest items that are found later in the AC affect the odds - if at all?

The only limitations I know of are:

- If you've found a Providence once, it cannot spawn again.

- An Iris Treasure and Providence are mutually exclusive drops.

Everything else seems random.

I'm done with all categories now, but pasting the info in here looks horrible and is a bit too much. So I'll have to find a place to upload it.

A few interesting things I found:

- All Blue Treasures are supposed to have an equal chance of spawning, but due to a restriction of the Random Number Generator, some items spawn lightly more often than others. These items are: Blaze sword, Gloom jewel, Gorgan rock, Ice hairband, Ruse armor (haha), Sea ring, Sizzle sword, Snow sword, Water gaunt, Water jewel. They all have a 0.053% chance of spawning where others have 0.046%. That's a 16.64% difference.

- This same restriction makes the Cursed bow more rare (0.128%) than the Myth blade (0.149%) even though you can find the Cursed bow 10 floors sooner (50-98 vs 60-98).

- The only non-blue armor piece you will ever find on floor 10 is an Apron.

- The most common items are: Potion, Hi-Potion, Ex-Potion (5.596%, 4.222%, 3.621%)

- The most rare items are: Circlet, Golden helm, Gold band, S-power ring. They all have an average spawning chance of 0.001%; they only appear at floor 9 with a 0.008% chance. On average you will need to do 182 AC runs (past floor 9) to find one.

All Weapons and Armor odds are floor dependent, so I averaged the odds for each floor so you can't use them for any fancy binomial probability calculations etc.

On Treasure Rooms:

Treasure Rooms have a 3.5156% chance of appearing per floor. These rooms contain:

- 12 enemies

- (8 - [number of chest outside the room])

There's nothing special about the chests spawned, so you could theoretically get 8 blue chests in one Treasure Room. I have no idea what happens if the floor is too small to fit all those chests and enemies though :p.

While searching for this info I also noticed that the HP restoring tiles also have a 3.5156% chance of appearing per floor.

Let me show you my gelatin gestures! - The Master