Throughout the expansions ofFinal Fantasy 14, it is slowly revealed that there are many worlds. The world players know the most is the one they live on, the Source. In Shadowbringers, they also got a close look into the First. Fans also know of the Void, which used to be the 13th world. In total, there are 14 worlds which are all fragments of what used to be Etheirys.
The Ascians worked to destroy these reflections, and every destruction of one of these worlds manifested as a Calamity on the Source (though Ascians had to help cause this Calamity on the Source as well for the Rejoining to work). This was done for them to rejoin with Zodiark and remake Etheirys. Some of these worlds are fallen, some are safe, and others are lost. With Endwalker finished, it is likely that these other worlds will be further explored.
Final Fantasy 14: The Differences And Commonalities Between Sin Eaters And Voidsent
The First was a world that was saved through the Shadowbringers expansion. The Ascians attempted to destroy the world by flooding it with light-aspected aether. Minfilia's intervention, with the help of Hydaelyn, stopped the flood and the Warrior of Light and their companions intervened by defeating Emet-Selch and the light-aspected monstrosities called sin eaters that plagued the land. This is the only reflection that was actually saved from doom.
The Second shard had a successful Rejoining. The Ascians destroyed it with fire-aspected aether, which ended the world while also creating the third Calamity on the Source. Since the shard was destroyed with fire aether, the Source's Calamity had the sun enlarge and spread wildfires throughout Eorzea. This is what made Thanalan a desert. The Third shard was also Rejoined with Zodiark. It
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