I have 11 and need one more, but i cant find it. There are two more question marks on the map. One of them is in the vault with the armour piece (which needs all the passkeys to enter) and the other is the grenade updgrade at the final boss fight (giant ship). Using the process of elimination it has to be the one in the vault but i need the passkey to get in. Can anyone tell me how to get this last passkey? Im sorry for writing so much and thank you for your time.