Muster the Departed is a uncommon Enchantment card from Modern Horizons 3 (MH3), collector number 36. Current market price: $0.29 (foil $0.29), TCGplayer market prices via Scryfall.
When this enchantment enters, create a 1/1 white Spirit creature token with flying. Morbid — At the beginning of your end step, if a creature died this turn, populate. (Create a token that's a copy of a creature token you control.)