Russian Submarine

The Russian Submarine contains the highly sought after Dead Hand nuclear missiles. Years prior to our present-day storyline, Mason parachutes onto the sub and installs a device that enables Citadel to have backdoor access to the sub. However, unbeknownst to even Citadel, Mason installs an additional device linked only to his biometrics that enables access to the sub. In the present-day storyline, Dahlia seeks control of the Dead Hand nukes, leveraging Asha in order to compel Kyle to parachute onto the sub so that Davik can gain entrance and secure the nukes.