Thomas Wagner is from Trost District. A member of the 104th Trainees Squad, he first meets Eren Yeager while questioning him about the Colossal Titan. Later, he operates the training gear for the Three Dimensional Maneuver Gear during Eren's second attempt at his aptitude test. At Keith Shadis' orders, Thomas exchanges gear with Eren and it is discovered that Eren's gear was defective. After graduating, Thomas plans to join the Scouting Legion.