Narratively, a sequel to both Xenoblade 1 & 2 at the exact same time that takes place in a world that was merged together from each of their own.
Play as 6 soldiers from the opposing nations of Keves and Agnus, joined together through the power of Ouroboros. Watch as they use this mysterious power to liberate themselves and everyone else from the evil Moebius.
Together, they shall overall learn more about their hybrid world called Aionios, a world populated by people that have only ever known, lived, and died by the endless cycle of war.
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I recommend checking out Xenoblade 1 & Xenoblade 2 if you want to understand the sheer volume of material that came from those games to build this one, from locations to story beats to even game mechanics and certain returning characters! I will provide links to them all, below!:
Xenoblade Chronicles: Definitive Edition (for Keves Context):
youtube.com/playlist?list=PLyLyf5pa2_KaDbMETCtwf55…
Xenoblade Chronicles: Future Connected (for additional Keves Context):
youtube.com/playlist?list=PLyLyf5pa2_Kaz6tC6HTSHbC…
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Xenoblade Chronicles 2 (for Agnus Context):
youtube.com/playlist?list=PLyLyf5pa2_KZn3jF-68o-6t…
Xenoblade Chronicles 2: Torna ~ The Golden Country (for additional Agnus Context):
youtube.com/playlist?list=PLyLyf5pa2_KZAUL0KAUSTuI…