Mana Vault [Kaladesh Inventions] Goblin Shaman If both targets are still

If both targets are still legal as this ability resolves

you may add an amount of {C} equal to the number of creatures you control that share a creature type with it

They don't untap during their controller's next untap step

You may reveal that card

Mana Vault [Kaladesh Inventions] Goblin Shaman If both targets are stillSet: Kaladesh Inventions Type: Artifact Rarity: Mythic Cost: {1} Mana Vault doesn't untap during your untap step. At the beginning of your upkeep, you may pay {4}. If you do, untap Mana Vault. At the beginning of your draw step, if Mana Vault is tapped, it deals 1 damage to you. {T}: Add {C}{C}{C}.