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 - $2,102.80
Lightly Played - $1,892.50
Played - $1,472.00
Heavily Played - $1,261.70
Damaged - $1,051.40
Near Mint Non-English - $2,102.80
Lightly Played Non-English - $1,892.50
Played Non-English - $1,472.00
Heavily Played Non-English - $1,261.70
Damaged Non-English - $1,051.40