Darren Cross was the CEO of Cross Technological Enterprises, a direct competitor of companies like Stark Enterprises, Trask Industries, and Oscorp. Darren was a successful self-made man but after realizing that he was suffering from a rare heart condition, he underwent a radical surgical procedure Since realizing that he was suffering from a rare heart condition, Darren Cross underwent a radical surgical procedure. Dr.Erica Sondheimimplanted an experimental but sophisticated nucleorganic pacemaker in order to prolong Cross’ life. However, Cross’ implant increased the size of his entire circulatory system and as a result, it mutated his body.
With the heavy toll brought on by the implant, Cross had undergo a continuous lapse in heart transplants and since an ordinary human heart could not sustain his augmented body, Dr. Sondheim would have to alter each donor’s phisiology
Sondheim was trailed by Scott Lang, a man who had stolen Hank Pym‘s Ant-Man suit in order to save Sondheim, who was the only person who could perform life-saving surgery on his daughter,Cassie. Cross battled Ant-Man, and died from the resulting stress caused to his heart. The company was later taken over by Darren’s son, Augustine, and his brother, William.
Years later, it was revealed that Augustine Cross, the son of Darren Cross, inherited Cross Technological Enterprises and had put his father’s body in suspended animation. At one point, Augustine kidnapped Dr Erica Sondheim and forced her to operate on the body of his father and transplant another stronger heart inside his body. This heart came from Cassie Lang, Scott Lang (Ant-Man)’s daughter. The theory was that her heart could take on the stress of Cross’ body because it was exposed to Pym Particles. Reluctant, Sondheim agreed and put a new heart inside Cross’ body. Cassie received a new heart of her own as well. Cross soon stood up and eventually fled the scene after a battle with Scott Lang (Ant-Man).
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