I rule that you get to choose one 'brain' eaten and so class feature or some other feature listed. Thrallherd is big no, but what you would assume from tarrasque? Also yes, wish would work empty class feature slot.<br/><br/>Anyways Kunoichi; you do not loose your powers/abilities, just that savant mind flayer does not get to keep the powers long as he could. I just try avoid your going offering your brains eaten across cosmos to mind flayer savants to dine upon in return of payment/favor :P. Some would do it even if it's temporal while others would not bother.