Tsabo's Assassin is a rare Creature — Phyrexian Zombie Assassin card from World Championship Decks 2001 (WC01), collector number ar128sb. Current market price: $0.98, TCGplayer market prices via Scryfall.
{T}: Destroy target creature if it shares a color with the most common color among all permanents or a color tied for most common. A creature destroyed this way can't be regenerated.