Reminds me of a friend's joke character, "Lummox McBigbrute, of the McBigbrute Clan from Thugginbourg". He had things like "Weapon Proficiency: Tree", a negative Int score, and an immunity to mind-affecting spells and effects.
Because you can't affect something that doesn't exist?
"If it lives it can be killed.
If it is dead it can be eaten."
Ronkong Coma "the way of the bookhunter" III Catacombium
(Walter Moers "Die Stadt der träumenden Bücher")