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}.
NM-Mint - $50.70
Lightly Played - $45.60
Moderately Played - $40.60
Heavily Played - $35.50
Damaged - $25.40
NM-Mint Non English - $50.70
Lightly Played Non English - $45.60
Moderately Played Non English - $40.60
Heavily Played Non English - $35.50
Damaged Non English - $25.40