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 - $0.95
Near Mint Non-English - $0.95
Lightly Played - $0.90
Lightly Played Non-English - $0.90
Moderately Played - $0.76
Moderately Played Non-English - $0.76
Heavily Played - $0.57
Heavily Played Non-English - $0.57
Damaged - $0.47
Damaged Non-English - $0.47