Cheapest priced copy (Mirage): $0.35 at Card Kingdom, near mint, their price list as of .
Urborg Panther 
Creature — Nightstalker Cat · 2/2 · Common · Mirage · #150
{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.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern