2 things :

1- If the item is currently in the game, then it’s the DM that have put them there in the first place. It’s fine to take them away if you made a mistake, but it’s your mistake, better own to it. 2- This is hilarious as I just gave my players a blank check where they can get any item whatsoever. Only one. But I’m waiting with excitement on what they will end up with.

Dude I once put the Fighter into a vegetative state because of an intelligence level of -1. He tanked all the magic damage with his shield of weaving, but not the effects.

Let them cook, the result is almost guaranteed to be amusing.