The Central Elevator Hall, often called just the elevator hall, is a circular vertical hallway containing an elevator which rises 50 meters to the surface of the Nevada Desert. It is the only way to leave the Underground Shelter. However, it is blocked by an X-Door connecting to the lounge. In order to get to it, the players must decide which of the others to kill in order to gain X-Passes to open the X-Door.
Story
D-END: 1
This is the only ending in which the central elevator hall is actually seen (in other endings, players escape through the X-Door but the central elevator hall isn't depicted).
Phi gets the idea of using the bomb from the Manufacturing to blow open the auxiliary exit in the Decontamination Room. After doing so, D-Team escapes, although Sigma is injured.
On the other side of the Decontamination Room door, the team meets the dying Q-Team. As they speak, Mira takes revenge by injecting Phi with the Radical-6 virus she took from the Biolab. Diana cannot face killing Phi and so takes Phi and Sigma out of the facility on the elevator, releasing Radical-6 via Phi in the process. Sigma realizes that this is the timeline that leads to Virtue's Last Reward, and comments "perhaps the next Sigma will do better." After this the three survivors are taken to a hospital where Radical-6 spreads.