Grafted Exoskeleton is a uncommon Artifact — Equipment card from Scars of Mirrodin (SOM), collector number 162. Current market price: $7.08 (foil $35.42), TCGplayer market prices via Scryfall.
Equipped creature gets +2/+2 and has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Whenever this Equipment becomes unattached from a permanent, sacrifice that permanent. Equip {2}