Ardbert, Warrior of Darkness 
Legendary Creature — Spirit Warrior
Whenever you cast a white spell, put a +1/+1 counter on each legendary creature you control. They gain vigilance until end of turn. Whenever you cast a black spell, put a +1/+1 counter on each legendary creature you control. They gain menace until end of turn.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL