Killer Service is a rare Enchantment card from Murders at Karlov Manor Commander (MKC), collector number 174. Current market price: $0.40, TCGplayer market prices via Scryfall.
When this enchantment enters, create a number of Food tokens equal to the number of opponents you have. (They're artifacts with "{2}, {T}, Sacrifice this token: You gain 3 life.") At the beginning of your end step, you may pay {2} and sacrifice a token. If you do, create a 4/4 green Rhino Warrior creature token.