Slinking Giant 
Creature — Giant Rogue
Wither (This deals damage to creatures in the form of -1/-1 counters.) Whenever this creature blocks or becomes blocked, it gets -3/-0 until end of turn.
Legality
standardNOT LEGALpioneerNOT LEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL