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.
{Tap}: Add

• Number: 17
• Rarity: S
• Type: Artifact
• Mana cost: 1
• Color: Artifact
• Artist: Kirsten Zirngibl