Mesmeric Fiend 
Creature — Nightmare Horror
When this creature enters, target opponent reveals their hand and you choose a nonland card from it. Exile that card. When this creature leaves the battlefield, return the exiled card to its owner's hand.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL