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 - $155.10
Near Mint Non-English - $155.10
Lightly Played - $139.60
Lightly Played Non-English - $139.60
Played - $108.60
Played Non-English - $108.60
Heavily Played - $93.10
Heavily Played Non-English - $93.10
Damaged - $77.60
Damaged Non-English - $77.60