Nekron
The force behind the Blackest Night event, a force so powerful that he was able to trap the Anti-Monitor in the Power Battery of the Black Lanterns, Nekron is the ruler of a dimension bordering Hell, Limbo and Purgatory. As such, his draws his power from those awaiting beyond life, whether heroes of villains. His final purpose can be considered great in scope "“ restoring order where chaos is. However, he intends to do that by ridding the universe from all emotions. And this can be done by ridding the universe from life.
Nekron can manipulate reality on a planetary scale and was able to kill even Guardians of the Universe. His power is so tremendous that he was able to recreate Krona in his own dimension and send it to battle the superheroes. In this way, he can be said to be above many of the supervillains on this list.
As the leader of the Black Lantern Corps, he is also one of the strongest there is, being banished only after the combined power of the entire light spectrum is pitted against him.
Sure, he needs a link between his dimension and the dimension of the living in order to exist in the mainstream universe. But this is hardly a weakness, right?
What do you think? Which villains can defeat absolutely anyone? Did we miss any obvious examples? Have your say below!

