Urborg Panther is a common Creature — Nightstalker Cat card from The List (PLST), collector number MIR-150. Current market price: $0.16, TCGplayer market prices via Scryfall.
{B}, Sacrifice this creature: Destroy target creature blocking it. Sacrifice a creature named Feral Shadow, a creature named Breathstealer, and this creature: Search your library for a card named Spirit of the Night, put that card onto the battlefield, then shuffle.