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 - $370.80
Near Mint Non-English - $370.80
Lightly Played - $333.70
Lightly Played Non-English - $333.70
Played - $259.60
Played Non-English - $259.60
Heavily Played - $222.50
Heavily Played Non-English - $222.50
Damaged - $185.40
Damaged Non-English - $185.40