Worldgorger Dragon 
Creature — Nightmare Dragon
Flying, trample When this creature enters, exile all other permanents you control. When this creature leaves the battlefield, return the exiled cards to the battlefield under their owners' control.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL