DominionStrategy Wiki
Iirc, this one's pretty much a nombo - it performs hardly better than straight vault.
{ name: 'DoubleVault' requires: ['Vault'] gainPriority: (state, my) -> [ "Province" if state.countInSupply("Gold") > 0 "Duchy" if 0 < state.gainsToEndGame() <= 5 "Vault" if my.countInDeck("Vault") < 2 "Estate" if 0 < state.gainsToEndGame() <= 2 "Gold" "Silver" ]}
{ name: 'DoubleVaultCaravan' requires: ['Vault', 'Caravan'] gainPriority: (state, my) -> [ "Province" if state.countInSupply("Gold") > 0 "Duchy" if 0 < state.gainsToEndGame() <= 5 "Vault" if my.countInDeck("Vault") < 2 "Estate" if 0 < state.gainsToEndGame() <= 2 "Gold" "Caravan" "Silver" ]}