After the Vault Hunters kill a Lost Legion Courier, the Lost Legion decide to place the next inside a powersuit. However, the Courier is untrained with this powersuit and when confronted by the Vault Hunters, accidentally lowers the powersuit's massive shields rather than his intended attack. He then manages to figure out the suit enough to gain control.
Initially, the Lost Legion Powersuit Noob did not respawn upon completion of Red, Then Dead. The March 24th, 2015 patch made him respawn after the mission, but also unintentionally caused him to spawn before the mission is available/begun and also causes his intended dialogue and large shield when he appears during the mission to be non-existant.