Lord Croft's Secret Vault
Lord Croft's Secret Vault is a room in Croft Manor that can be visited in the Blood Ties DLC of Rise of the Tomb Raider: 20 Year Celebration.
Finding the Secret Vault
After Lord Croft's Safe did not yield a last will Lara has to decipher a clue left by her father Lord Croft instead. This clue consist if a map of the Wine Cellar - where the secret entrance to the vault is located - and three Hieroglyphs on the back that correspond to Egyptian provinces and can be decoded using the Hieroglyphics Worksheet. Thus the numbers "142" will be revealed Lara will need to enter into to keypad. A wall behind her will open onto a passage which leads to the Secret Vault. The door will close behind her and she will be trapped inside for a while until she figures out a way to leave.
The Vault
The Secret Vault is where Lord Croft studied his immortality artefacts. There are boxes of material neatly stacked along the rear wall, a big table where he would work, as well as some cabinets on the left side. There are several Documents and Relics that can be collected here, bit most importantly Lara will find the Crowbar here which she can use to break through the back wall in order to leave. Afterwards she can use the same crowbar to open the Lockers in the Wine Cellar.
Gallery
Turning on the black light reveals secret messages...
...e.g. a map-like drawing on the whiteboard...
...and additional markings on the boxes behind the table.
