Quote Originally Posted by TheMadLinguist View Post
Technically, they don't say "can be mentally damaged". They just say "cannot be physically damaged". So if you found a way to get a con score, you'd still be immune to physical damage, or if you found a way to count as the undead type, you'd be immune to physical but not mental damage.

Or if you lost your con as a non undead, you'd be immune to any ability damage.

Unless you have rulestext that says "undead lose any immunity to ability damage to their mental scores"?
It seems that on this piece on chicanery, you are technically correct.