The can be found four metal tabs that black is located in the cell of the fort where Aline meets Obed Morton, while the other three are in a crate in a hallway that separates the walls from the building's foundations. Thanks to the second part of Jeremy Morton's diary you can define a symbol associated with each card: a lightning that silver corresponds to that of the gold star, the red sun and the moon in the black. The code is then replicated by inserting the tabs into their respective slots of the planetary door, so that it can be opened.