Ahn-Crop Champion 
Creature — Human Warrior
You may exert this creature as it attacks. When you do, untap all other creatures you control. (An exerted creature won't untap during your next untap step.)
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL