You know… if you’re having trouble picking between regular and mycus mutations, you could always get the best of both by duping those fungal jerks. All you have to do is get the Marloss Carrier trait BEFORE doing any of that mutagen stuff. After that, you’re free to go down whatever mutation path of your choice, and as a bonus, you don’t even have to worry about accidentally purifying away the marloss trait.
However, whatever you do, NEVER chug down or inject just pure mutagen/mutagenic serum. Really bad, potentially lethal stuff will happen. Every other types of mutagens//purifiers/serums are ok, though (all under perscribed dosages, of course).