Psychic hunters cannot spawn if you have any mutations that are not included in Mutations.xml

[Mawootad]

If you have any mutations that aren’t in mutations.xml, such as if you are in the body of a monster that has monster-only mutations, psychic hunters will not spawn. The cause of this is that GetMutationEntry returns null on any mutations not in mutations.xml and the methods for generating psychic hunters then use the return from GetMutationEntry without checking if it is null. This also breaks some mods, specifically WM Mutations Extended currently is affected by this as it adds a mutation to manage interactions between some other mutations which is not in mutations.xml.

[Noelle Lavenza]

While found via a mod, I'm told this could potentially happen in the vanilla game if the player somehow obtained Heightened Smell (e.g. through bodyswapping) or any other mutation without an entry in mutations.xml. This could also cause issues with anything that uses GetMutationEntry() and doesn't check for null, but this is thankfully the only case in the vanilla game I've found so far.

[Mawootad]

Of particular note, this means that Cloaca Surprise permanently disables psychic hunters, as it the Bilge Sphincter mutation that it grants is not in mutations.xml

[Armithaig]

Fixed in 201.115