Rave Master

From the introduction:

It has been 50 years since the war between Symphonia and Raregroove. When the Rave Master, Shiba Roses, destroyed the mother Dark Bring, Sinclaire, in an effort to end the war, it created an explosion powerful enough to destroy a tenth of the world. OK, maybe the history books exaggerated some. Really, it was only a tenth of the known world of the time. Still, it did destroy both countries, and basically the entire continent. Shiba was the only survivor. Unfortunately, the dark bring were not destroyed and were instead scattered across the world, along with four of the rave stones.