Rukarumel, Biologist is a mythic Legendary Creature — Human Wizard card from Commander Masters (CMM), collector number 776. Current market price: $5.88 (foil $15.64), TCGplayer market prices via Scryfall.
As Rukarumel enters, choose a creature type. Slivers you control and nontoken creatures you control are the chosen type in addition to their other creature types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield. {3}, {T}: Create a 1/1 colorless Sliver creature token.