Skaarin is definitely my favorite I've written so far. (And one of the few I've created, because there's so few heroes in my world.)
Skaarin created a way to make his body regenerate any wound. And goes far enough to do this to the main character, meaning neither of them can die now!
He's gone through a lot in his past, and when he was finally ready to settle down, his family was murdered during a war by his king. He tried for years on end to work through the kings ranks and get close to him to earn revenge, but he was sent off to watch King Alucin's son. The king died during this time, leaving Skaarin's life as empty as it could become. He fell back to research and learning, and used prisoners as test subjects, even stealing someone else's body, because his was aging.
He is ruthless, broken, has violent and gory fits when he's ecstatic, and he's cunning. But most of all, he's patient. As a man who's lost everything and can't die, he has no fears. And he's able to get what he wants. At least, until new wants arise...
Skaarin is a blast to write! In fact, he was such a big piece in Part One that when I realized he wouldn't be back until the third and final part of my story, I changed my ideas entirely. Part One has fast-paced pov changes between the protagonist and villain. (Lucrys and Skaarin.) And I let this flow and explode, because they're both so mentally broken, that breaking some rules of storytelling almost needed to be done to truly manifest their characters. Part two is about Lucrys. And Part Three is dedicated to Skaarin at their split. Until the final chapter where they finally meet again.
This is totally like Temorra. I call him "The Man of Debt." xD However, he's not so harsh with it. If you wrong him, he'll use you for help, or harm you somehow. But he goes both directions. If he harms someone or someone does something for him, he'll always make sure to return the favor and make it up to them the best he can. Or... in any way he feels is equal, at least. xP