[Fan Theory] The entire series takes place in Astral Chaos

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An explanation for the massive amount of ludonarrative dissonance that has been a part of the series since the beginning.

Planet Earth was doing just fine existing with dimensional stability in Soul Calibur's primary universe. But when Soul Edge was defeated by Taki it became furious! It allowed the entire planet to sink in to Gap Of The World. Ever since then Soul Calibur's main world has existed in Astral Chaos. Civilians are not even cognizant of their situation. They explain their situation through The Evil Seed events, but what is really happening is that the laws of physics are degrading over time. The entire planet is becoming a battlerealm.

This is why each Soul Calibur game has the exact same recurring locations that do not change until the next game. The player is exploring different parts of the battlerealm. This is why there are so many extra characters who are based on the primary characters. It is even how mimic characters are able to emulate multiple characters. Your character in Libra Of Soul has found a way to tap in to this and use any primary character's base even Azwel.

And the guest characters. How is it that Soul Edge is able to summon even some of the Star Wars characters? By sucking planet Earth in to Astral Chaos, Soul Calibur's world can access many different multiverses. Perhaps this even explains the light sabers not functioning as normal.