In a bid to destroy the Avengers from within, Baron Zemo performed ionic energy experiments on a man named Simon Williams. The experiments succeeded beyond Zemo's wildest dreams, transforming Simon into a being of superhuman strength and durability. Simon was welcomed into the Avengers as Wonder Man and became a spy for HYDRA. Later, he threw off HYDRA's control, saving the Avengers and truly becoming one of them. While his nigh-invulnerability has let him overcome physical challenges with ease, he continues to struggle with the ethics of using his tremendous gifts, endeavoring to pressure his humanity in the face of his own immortality.
Current Version:
Wonder Man (Modern)