Drowsing Tyrannodon 
Creature — Dinosaur
Defender (This creature can't attack.) As long as you control a creature with power 4 or greater, this creature can attack as though it didn't have defender.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL