Spiritmonger is a rare Creature — Beast card from Conspiracy (CNS), collector number 193. Current market price: $0.15 (foil $0.40), TCGplayer market prices via Scryfall.
Whenever this creature deals damage to a creature, put a +1/+1 counter on this creature. {B}: Regenerate this creature. {G}: This creature becomes the color of your choice until end of turn.