Liege of the Pit is a rare Creature — Demon card from Time Spiral (TSP), collector number 113. Current market price: $0.75 (foil $2.51), TCGplayer market prices via Scryfall.
Flying, trample At the beginning of your upkeep, sacrifice a creature other than this creature. If you can't, this creature deals 7 damage to you. Morph {B}{B}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)