Tsabo's Assassin is a rare Creature — Phyrexian Zombie Assassin card from Invasion (INV), collector number 128. Current market price: $0.67 (foil $5.00), 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.