Rathi Assassin is a rare Creature — Phyrexian Zombie Mercenary Assassin card from Nemesis Promos (PNEM), collector number 67. Current market price: — (foil $4.55), TCGplayer market prices via Scryfall.
{1}{B}{B}, {T}: Destroy target tapped nonblack creature. {3}, {T}: Search your library for a Mercenary permanent card with mana value 3 or less, put it onto the battlefield, then shuffle.