Simon Williams was an industrialist who inherited his fathers munitions company, but profits fell due to his biggest competitor, Tony Stark. After trying to embezzle funds from his own company (under the advice of his brother), Simon was incarcerated and blamed Stark. So when he was given the chance to exact revenge, he accepted it, allowing Baron Zemo to grant him superhuman powers via ionic energy. But after leading the Avengers into a trap, Wonder Man turned on Zemo and sacrificed himself to save the Avengers. Despite dying in his first appearance, Wonder Man would be resurrected and gain Avengers membership over a decade later. But even before that resurrection, his death hung over the book. Tony Stark had recorded Simon Williams brain patterns in the hope that he could be revived, and these brain patterns were used by Ultron as a template for the Vision. Simons brother, Eric, also became the Grim Reaper and a regular enemy of the team. After his revival, Wonder Man became close friends with the Beast and later joined the West Coast Avengers and Force Works, where he was killed again. But once more, Simon was resurrected by the Scarlet Witch and became a regular member of the team. Hes appeared in 273 issues to date. Although he briefly went uncharacteristically insane for no real reason and attacked the Avengers, Simon since reformed and joined the Avengers Unity Squad, planning not to fight but to only help with his PR skills. But in allowing Rogue to absorb his powers, Simon appears to once again be among the dead. As of now, Wonder Man is the only Avenger on this list who is not slated to appear in a Marvel film. Hopefully that changes soon.
Percival Constantine is the author of several novels and short stories, including the Vanguard superhero series, and regularly writes and comments on movies, comics, and other pop culture. More information can be found at his website, PercivalConstantine.com