Tyranid Prime 
Creature — Tyranid
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.) Synapse Creature — Other creatures you control have evolve.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL