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}.
Near Mint - $81.60
Lightly Played - $73.40
Played - $57.10
Heavily Played - $49.00
Damaged - $40.80
Near Mint Non-English - $81.60
Lightly Played Non-English - $73.40
Played Non-English - $57.10
Heavily Played Non-English - $49.00
Damaged Non-English - $40.80