The sealing of alchemy and creation of lighthouses (021)
Back when alchemy was about to be sealed, the Jenei and the Exathi tried figure out how to do it the safest way possible. Eventually, they came to the conclusion that the Exathi would build four lighthouses, each corresponding to one element and the Jenei would guard the elementals stars that would be the keys to ignite those lighthouses in order to release alchemy again if needed. The Jenei hid the stars inside a volcano protected by psynergy. They then settled down in a village by the foot of the volacno and named it Vale.
After building the lighthouses, the Exathi settled down somewhere nearby them and guarded them just like the Jenei guarded the elemental stars. The Exathi settled down in small towns and named them Imil, [unknown name], Anemos and Prox. The elemental lighthouses affected the psynergy of the Exathi which is why they developed into the clans we know as Mercury, Venus, Jupiter and Mars.