Captain Cold

Leonard Snart, better known as Captain Cold is a former villain, who eventually became a good guy.

Story Involvement
Captain Cold comforted Wally West when he was visiting Barry Allen's grave, and has since then become a good guy.

When Gang Weeders took Harvey Dent hostage, along with Rachel, he tried to ultimately save Rachel, but he caused her death, as a complete opposite of what he was trying to do.

Since then, Captain Cold has been doing heroic stuff, like stopping bank robberies and active crimes.