The Area Of Doom is a theorized part of the known Omniverse where rift activity is the most frequent. It is said that it is made up of a large network of rift filled areas,that is slowly spreading to nearby universes. It has yet to reach space outside the Multiverse fortunately.
Aside from these locations, it has been observed that rift activity and Omniversal collapse are most common on the outermost edges of the Multiverse, there are some rift hotspots in the center however.
Multiversal legends say that the worst things in the Omniverse exist in the areas most affected by rifts. It is also believed that the most rift infested places are the breeding grounds of cosmic horrors. No one really knows if these legends are true because no one dares to tread near these places due to their high rift activity, along with other unknown dangers lurking.