Prosper, Tome-Bound [The List] Theros Beyond Death Tokens they play it without paying

they play it without paying its mana cost

Set: Innistrad: Crimson Vow Type: Legendary Creature — Vampire Rarity: Mythic Cost: {2}{B}{B} Flying

Clear front & Blue back

Set: Urza's Saga Type: Creature — Avatar Rarity: Rare Cost: {4}{W}{W}{W} Serra Avatar's power and toughness are each equal to your life total

Set: Streets of New Capenna Commander Type: Enchantment — Aura Rarity: Rare Cost: {U}{U} Split second (As long as this spell is on the stack

Prosper, Tome-Bound [The List] Theros Beyond Death Tokens they play it without payingSet: The List Type: Legendary Creature Tiefling Warlock Rarity: Mythic Cost: {2}{B}{R} Deathtouch Mystic Arcanum At the beginning of your end step, exile the top card of your library. Until the end of your next turn, you may play that card. Pact Boon Whenever you play a card from exile, create a Treasure token.