Because I wanted there to be a 'Screw You' universe. Not really expecting anyone to go here, I just like the idea of the one universe every inter-universal being avoids, no matter what.

Name: The Doomsday Universe (alternate DCU)
Scale: Usually described as 'Oh holy mother of f*ck no"
Setting: Everybody is doomsday. Take the entire DCU. Now replace every character with a similarly themed Doomsday clone. The civilians are FTL death machines that could one-shot Apocalypse, and Doomsday Superman.... well, it's Doomsday Superman. These characters are all currently fighting amongst themselves, dying and recreating one another over and over again, as entire armies of doomsdays fight over a span of galaxies, even as the divine beings barely keep the universe intact.
History: 
In this alt timeline, Doomsday was never developed as a creature. Instead it was developed as a disease, a special infection that could transform any creature into Doomsday. While this was sealed away by the Green Lanterns many years ago, it was released at more less the same point in time as the Superman Doomed event in standard DCU. It rapidly spread across the universe, as entire races were turned into Doomsday monsters. There were those with a cure, but they were killed by the THOUSANDS OF DOOMSDAYS. Now there is only war, awaiting the arrival of the mythical 'Doomsday Prime'. This being would be the ultimate form of Doomsday, a perfect being with unlimited strength and speed, who would devour the entire universe and kill everything.

There are several Doomsday Factions, including the Doom Lanterns and the Doom Skrull. These Doomsdays have started working together, adapting the capability for cooperation as they wage war on other doomsday subspecies.

Power Scaling: IT'S OVER 900000000000000!!!!!