So I was reading another RFE on Mindcrafters, and had an idea that could combo with it.

(Credit for this portion of the idea goes to plllizzz9, RFE 1726) First, as a late game ability (maybe level 40 or so?) give them "mind control". This would effectively turn a monster tame for a number of turns, and would only work on one creature at a time. The chances of success would be determined by the intelligence of the creature and the willpower of the PC, and the mind control would run until deactivated or until the Mindcrafter runs out of power points. Attempting it on undead as usual would injure the PC, and attempting it on a demon or corrupted creature would corrupt the PC. Naturally some or most uniques would have to be immune for functional reasons.

Spinning off that, as an endgame ability (at or around level 50, probably), they would gain "possession". This would allow the player to control a monster directly as if they were controlling their own PC. Again the chance of success would be dependent upon the player's willpower and the monster's intelligence. It would drain a huge amount of PP, and the check for success would be run every game turn, making it a constant battle of wills whether the mindcrafter maintains their hold or whether the monster wrestles back control of their body. I'd suggest making a (large) prerequisite willpower level before this power even became available (maybe Wi:40?). Same rules regarding corruption, undead, and uniques apply as earlier.

This would give mindcrafters a completely new, dynamic strategy to use, and at the same time, they'd have to be very careful in its execution as the PC would be defenseless while possessing something else and could easily be killed if they're out of LOS and don't realize their body is being attacked. I would even suggest that if they attempted to use it on a powerful demon (greater demons, balors, molochs) there might even be a chance that it could backfire, give the demon a door into their own mind, and end up possessed themselves for a number of turns (a little like being confused, where the player has no control over their movements and can only watch, but more directed as they'd be moving and acting with the behavior of a monster instead of randomly).

Probably tough to implement (possession, anyway), but I think mindcrafters have so much untapped potential as a class, and this power would be so much fun, I wanted to suggest it anyway. Just in case.