Mnemonic Betrayal [Guilds of Ravnica] Planechase Planes search your library for a

search your library for a creature card with power 2 or less

it gets +3/+3 until end of turn for each creature blocking it beyond the first

That token gains haste

Set: Revised Edition Type: Artifact Rare Cost: {1} Mana Vault doesn't untap during your untap step

If you can't

Mnemonic Betrayal [Guilds of Ravnica] Planechase Planes search your library for aSet: Guilds of Ravnica Type: Sorcery Mythic Cost: {1}{U}{B} Exile all cards from all opponents' graveyards. You may cast those cards this turn, and you may spend mana as though it were mana of any type to cast those spells. At the beginning of the next end step, if any of those cards remain exiled, return them to their owners' graveyards. Exile Mnemonic Betrayal.