Annex Sentry is a uncommon Artifact Creature — Phyrexian Cleric card from Phyrexia: All Will Be One (ONE), collector number 2. Current market price: $0.26 (foil $0.37), TCGplayer market prices via Scryfall.
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.) When this creature enters, exile target artifact or creature an opponent controls with mana value 3 or less until this creature leaves the battlefield.