X-51 is rebooted in the body of an FBI Life Model Decoy, with pretty impressive new powers. He’s moved from the Jack Kirby vision of the character, which was kind of like Silver Surfer as a robot (constantly conflicted with the meaning of being human) to being a self-aware life-form who will do whatever he needs to do to preserve his own life.
He also is aware of the threat presented by the Sentinels because he now has some Sentinel tech in him. He contemplates approaching Cable, who is from one such version of that future, but can’t figure out how to find him–so he goes to Avengers Mansion. Only Firestar and Justice are home, and they think he’s attacking.
He takes on the duo and then Vision.
During that battle, X-51 realizes that inside him is corrupting Sentinel tech that could, if expanded beyond his personal robotic frame, infect the entire planet. So, Bastion essentially turned him into a sleeper agent.
I’m really enjoying this series!