Warden of the Beyond 
Creature — Human Wizard
Vigilance (Attacking doesn't cause this creature to tap.) This creature gets +2/+2 as long as an opponent owns a card in exile.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL