From the Vault: Vaults

, : Exile target creature you control.
, : Exile target creature you don't control.
When Helvault is put into a graveyard from the battlefield, return all cards exiled with it to the battlefield under their owners' control.

, : Exile the top card of your library face down.
: Sacrifice Knowledge Vault. If you do, discard your hand, then put all cards exiled with Knowledge Vault into their owner's hand.
When Knowledge Vault leaves the battlefield, put all cards exiled with Knowledge Vault into their owner's graveyard.

Mana Vault doesn't untap during your untap step.
At the beginning of your upkeep, you may pay . 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 to your mana pool.

Time Vault enters the battlefield tapped.
Time Vault doesn't untap during your untap step.
If you would begin your turn while Time Vault is tapped, you may skip that turn instead. If you do, untap Time Vault.
: Take an extra turn after this one.