X Krillin is a character created by UltimateGoku. X Krillin is in another parallel world from Majin Goku and the regular Goku. X Krillin is when Goku or Vegeta don't arrive to Earth making Krillin the strongest person in the world. And he takes over the world with evil corrupting him. And since the Z-Fighters don't really exist nothing can stop him. But Krillin in the regular worlds (with Goku) comes in a parallel world teleporter, he comes to defeat X Krillin. Even though they are the same person with the same moves, Krillin just barely defeats him. But then Krillin thinks "If I killed myself, wouldn't I die too?" but he doesn't care so he goes to the parallel world teleporter and thinking how he killed X Krillin, or so he thinks.
He looks like Krillin but his Gi is red and black with an X on it List of tecniques All of Krillin's moves but enhanced with Darkness (Ex.Dark Destructo Disk), he can do Kaio-Ken while he is unaware where he learned it.