Clamor Shaman 
Creature — Goblin Shaman
Riot (This creature enters with your choice of a +1/+1 counter or haste.) Whenever this creature attacks, target creature an opponent controls can't block this turn.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL