Dark Kahn (Mortal Kombat vs. DC Universe)

Dark Khan was created when Darkseid of the DC Universe was merged with Shao Kahn of the Mortal Kombat, due to a combination of Superman's heat vision destablising Darkseid's Boom Tube and Raiden's lighting bolt striking the portal as both enter it, this merged being was the focal point of what was refered to as the "world merge crisis" and had the powers of both and something else - Kombat Rage, which agitates the heroes and villains of both universes until they become enraged, which drives them to fight, which released the rage and hastened the merging of the two universes, which can make those affected see their friends or even the unfamiliar as their worst enemies.

His existance also had an additional side-effect, energies of the heroes and villains were being siphoned to others, making them stronger or weaker than normal. It also created energy rifts that make half of one part of earth appear on another (e.g. Themyscera and Shang Tsung's Island).

Dark Khan is the final boss in Mortak Kombat Vs DC Universe in a area which is a merged version of Apokalips and Outworld, consisting of Darkseids's and Shao Khan's palace split in two divided by an energy rift and large pieces of the world floating like asteroids (which for some reason have normal gravity). Once he is defeated, Darkseid and Shao Khan seperate and end up switching universes.