Purges

Purges are masses of destruction that rage across a certain dimension or universe, destroying everything. They are usually braut on by a victory either of Vaatu or Raava over the other. A Purge starts, leaving its starting point intact, then it rages as a growing sphere of Purge Fire, destroying everything it makes contact with. When it comes to a Universe, the Void Stuff protecting the universe from the void pops, and almost instantly the purge roars over and into the contents, killing and turning everything into Charconite, akin to a cold-wave coming across a water balloon. Once a Purge has swept through the entirety of its home dimension, it will emerge in the next dimension up. The only thing that can stop a purge is Exotic matter, which makes up the boundaries of reality. Sufficiently advanced races can coat the void stuff that is the boundary of their universe in Exotic Matter, protecting a sample of each defenseless race in a Walled Garden. 2nd dimensional races can seek refuge in Nursery universes which have a small membrane of Exotic matter enveloping them like a placenta, which will melt away and shatter under particularly strong purges. The Last Purge until the end of reality will be the strongest ever recoreded, and will utterly evaporate and combust all but the most heavily guarded and protected universes and pocket universes. The only main-reality universes to survive the Last Purge were the 5th dimensional world of the Katineth, the 4th dimensional Lego Universe, and the 2nd dimensional Home of the Akakals.