This article is about the train car. Did you mean the episode?
The Engine is the front of the train, featured in "The Engine".
After boarding the Infinity Train, Amelia Hughes eventually made her way to the Engine in her efforts to try and get a car with a version of her late husband Alrick in it. When the conductor, One-One, refused, she overthrew them and made her home in the Engine, becoming known as the Conductor while wearing a robotic suit to disguise her appearance. Amelia made many attempts to create a car that recreated her old life, including the Unfinished Car, but all were unsuccessful.
Tulip Olsen, on her journey through the train, came to the Engine in the commandeered Ball Pit Car after watching Amelia's memory tape and learning her true identity, accompanied by One-One, the Cat, and the Gohm-transformed Atticus. After the Cat's departure, Tulip and One-One, hauling the transformed Atticus behind them, entered the Engine by climbing through the new car still under construction. During the ensuing confrontation, the Steward, used by Amelia as her henchman, was destroyed, Atticus was restored to his true form and One-One was restored to their rightful place as conductor. After Tulip persuaded Amelia that her quest to bring back her husband in some form was futile, One-One re-opened Tulip's portal home in the Engine, as Amelia had sent the Ball Pit Car to the very back of the train to try and stop her. Tulip bid her farewells to Atticus and One-One before departing the Train for home.
The Engine, due to its location at the very front of the Train, has a streamlined profile to assist in its endless journey through the Wasteland. It also contains a mechanism for creating new train cars. The inside of the Engine is a large white room, with a console where One-One was normally plugged in while in control of the Train. During Amelia Hughes' reign as the false Conductor, she added a bed and sink, as well as a console where she could check the statuses of all other passengers.