Ichorclaw Myr is a common Artifact Creature — Phyrexian Myr card from Scars of Mirrodin (SOM), collector number 166. Current market price: $0.91 (foil $11.13), TCGplayer market prices via Scryfall.
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Whenever this creature becomes blocked, it gets +2/+2 until end of turn.