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 - $4,202.90
Near Mint Non-English - $4,202.90
Lightly Played - $3,782.60
Lightly Played Non-English - $3,782.60
Played - $2,942.00
Played Non-English - $2,942.00
Heavily Played - $2,521.70
Heavily Played Non-English - $2,521.70
Damaged - $2,101.50
Damaged Non-English - $2,101.50