The Only Traitor

The Only Traitor DLC is the first playable DLC of The Final Station. In it, you play as a man named Peter Glenn (A survivor from The Final Station) trying to make it to one of the shelters to escape the infection. In it, you drive across the land ravaged by war, picking up survivors, and dropping some off. Some old and new questions are answered in it, and combat features brand-new enemies, including human ones.

Features
These are just some of the new features to this game
 * An all-new playable experience for The Final Station
 * You get to drive a car
 * You only ever have to worry about one passenger at any given time (and feeding is automatic)
 * New locations (and some familiar ones)
 * Time and space are warped
 * New enemies, zombies and humans
 * Finally, a better idea as to what is really going on (but only a little bit)

Story
Peter is traveling in a car across the countryside, and is taking one companion at a time, provided their usefulness. As he goes further through the game, the Hunter and Armand White start to become more prominent. It is also discovered that Vermund White was locked up, tortured, and literally left to rot in a cell. In addition to this, the Hunter seems to serve an organization that is obsessed with the gas.

The player merely is a bystander in all of this until the very end, where they encounter a shadowy organization that is experimenting on people with the Capsules to make super-humans, but most of the experiments are failing. The protagonist is eventually found to be sneaking around but is rescued by the Hunter, who seems to be able to open another dimension that bends time and space. We see some of his work through broken bits of spatial time. He then sends the protagonist back in time (or across space, this isn't 100% clear) to kill the train conductor. The game ends with the protagonist being found by the train conductor at the underground station you visited in the first game. As the main game presents, the protagonist didn't follow the order of killing the conductor, which means he reaches a shelter safely through the conductor's train eventually anyway.