Kapow! 
Sorcery
Put a +1/+1 counter on target creature you control. It fights target creature an opponent controls. (Each deals damage equal to its power to the other.)
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL