Dirty Wererat 
Creature — Human Rat Minion
, Discard a card: Regenerate this creature.
Threshold — As long as seven or more cards are in your graveyard, this creature gets +2/+2 and can't block.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL