Demonlord of Ashmouth is a rare Creature — Demon card from Avacyn Restored (AVR), collector number 96. Current market price: $0.28 (foil $0.63), TCGplayer market prices via Scryfall.
Flying When this creature enters, exile it unless you sacrifice another creature. Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)