The Celstian War was caused by following the invasion of Tenebris into their land, which corrupted Celstis and caused them to turn into Daikura. A group of Celsti realized this and rigged the life core to detonate. The result of this was most of the Celsti and Daikura alike being destroyed and the Big Bang. Furthermore, the surviving Celstis were weakened and were about to pass away into The Shimmer. However, the Shimmer spoke to them, saying “You have done well to sway the destruction away, I do not wish to see another universe be completely destroyed. As such I will give you some of my power, so that your world will not become the same as mine,” (translated).