Tear or Rift

10,000 years before Modern day Mythrin A Giant island covered in crystals flying just above a volcano happened to get caught in an eruption. This resulted in the Island exploding creating a Tear or Rift in the fabric of reality dumping all sorts of life onto the World of Mythrin from other Planes and realities. This event is also rumored to have created The Rift Fragment and the Astria Islands.