Venerated Rotpriest is a rare Creature — Phyrexian Druid card from Phyrexia: All Will Be One Promos (PONE), collector number 192p. Current market price: $3.06 (foil $3.44), TCGplayer market prices via Scryfall.
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.) Whenever a creature you control becomes the target of a spell, target opponent gets a poison counter.