Doctor Robert Bruce Banner, M.D., Ph.D., was a scientist whose experiments with gamma radiation caused him to transform into Hulk. When Ultron obtained a new body, Hulk and the Avengers attempted to defeat him, only to fail and die by AI's hands.
Bruce Banner experimented with gamma radiation, causing him to transform into Hulk. He later joined the Avengers. Ultron began attempting to create peace in the world by destroying humanity, prompting Hulk and the other Avengers to attempt to fight him. They confronted Ultron at the NEXUS Internet Hub, where Ultron killed Hulk, who laid on the ground while Ultron took control of the world's missiles and succeeded in his goal, killing nearly all of humanity.[2]