7) Iron Lad
Nate Richards might be most known to Marvel fans as Kang the Conquerer, one of the most formidable opponents of the Avengers. However, a teenage alternate version of the villain has served time as a hero, leading the Young Avengers as Iron Lad.
First up, a bit of background. Hailing from the 30th century, Kang the Conquerer is really a descendant of Reed Richards AKA Mr. Fantastic. At one point, he revisits his younger self to ensure he transforms into the evil genius he is today. Unfortunately for him, it has the opposite effect. Young Nate is so horrified by what he becomes that he runs away to the 21st century in order to change his fate.
Iron Lad’s story is a strong one for exploring the themes of destiny and the immutability of fate. He might not be the longest-serving hero on this, list but he proved to be a fascinating sort of redemption for the supervillain.