There once was a man who made people better, or that's what he told himself. Sometimes, it was true. Sometimes he saved worlds, universes even.
Sometimes he didn't.
There once was a man who made people worse. He enjoyed what he did and sometimes it would just be people he hurt, sometimes worlds, sometimes even more than that.
The two men had been friends once, a long time ago, but not any more. They became enemies, chasing each other across the stars. It was this way for a very long time.
Then there was a war and suddenly, they found themselves on the same side, though neither knew it. Wars end though, just as this one did but the only one left standing was the man who made people better.
Although he had friends (he always had friends), he saw himself alone. There was no one like him any more and it left him lonely. He was wrong though, there was someone like him.
There was the man who made people worse, though, once again, neither of them knew that.
But everything fell back into patters soon enough, they chased each other, and this time, the man who made people worse seemed to gain the upper hand, at least for an entire year.
But that didn't last. With the help of friends, the man fell and everything was set to the way it was supposed to be.
And the man who made people better decided to do what he does best on the man who makes people worse.
At first, things weren't terrible, depending on your definition of the word, but the man who makes people worse is good at what he does, brilliant even and the man who makes people better? Well, he's determined to be good at what he does.
Measures are taken, drastic measures, but the man who makes people better knows it's for the best. He's doing this to fix the other, to make him good. He changes him, rewrites everything he is so that he can work with him more easily.
And the man who makes people worse? Well, he isn't that man any more. Instead he's something smaller than that, human and fragile and quite a bit mad.
And the other man? The one who makes people better? Well, he becomes his doctor, of course.