Help me find this

[EpsilonX]

Okay, so I remember at some point I either saw or played a game/movie/show where in it, the main characters are looking for something. There is a character who is very powerful, and was at one point bad, but decides to become good and helps the main character. However, there is a character who possesses something you're looking for (I don't remember what...either the object you're searching for or info about the object) and this character had been crippled or something like that by the bad-turned-good character. He begs for forgiveness and offers to let the person take revenge in order to show that he actually is a good guy now, but the guy decides not to take revenge and simply ends up helping them out instead.

Any ideas? I know it's vague, but if you can think of a game, show, film, or anything where an event occurs that fits this description, do tell. If you have any questions you need answered, i'll try to answer them. Please don't respond if you're going to just say "too vague" this has been bugging me all night and this is all that I can think of.