Who doesn't like a completely subjective Top 10 list? Here we go, my picks as the best villains-turned-to-heroes is as follows! I'm leaving out some characters that could technically be on here, but I don't think a single appearance as a threat to a hero is enough to label someone as a villain. For example, the Vision was created to destroy the Avengers but he quickly turned on Ultron, hence why I'm not counting him as a villain.
I'll start the countdown with numbers 10-6!
In Quicksilver's case, he can't seem to keep it straight if he is a villain or a hero. However, the Avengers always seem to accept him when he comes back to the side of good, though it's no surprise Pietro doesn't exactly have a lot of close friends. But does anyone expect the son of Magneto to be well-adjusted?