Psychic - Dark - Fighting is not a balanced triangle.
Perfect triangles are a pain in the ass. Its fine to just focus on one-way relationships. Qed greninja dark > delphox psychic > chesnaut fighting and primarina fairy > incineroar dark > decidueye ghost.
In fact, thats why id be opposed to psy/fgt/drk, been there done that. Try something new like... i dunno, ice/ground/rock? Or something?
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