Harvesttide Sentry 
Creature — Human Warrior
Coven — At the beginning of combat on your turn, if you control three or more creatures with different powers, this creature can't be blocked by creatures with power 2 or less this turn.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL