It would help if so much of it wasn't so self-contradictory & retconning past lore:
"Heartless have no hearts"
"Actually they're made out of hearts & pretty much the exact opposite of their name"
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"Also, nobodies are made out of bodies & are the ones devoid of hearts"
"Actually nobodies do have hearts"
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"The bad guy is Ansem"
"No he's not, the guy is Xehanort who is Ansem's apprentice"
"No he's not, Xehanort is a much older dude who was only apprentice for a short while & said apprenticeship is now a really minor footnote of his life story"
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"This world is called Hollow Bastion"
"No it's not, it's called Radiant Garden & is the capital of Light"
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"Vanitas is the dark half of Ventus' heart"
"No he's not & Ven is a dum dum for believing that even though it's what Vanitas told him!"
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"Maleficent was manipulating Riku to evil"
"No, it was Maleficent & Ansem"
"No, it was all Ansem Xehanort's heartless, Maleficent doesn't get credit for jackshit"
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"Chi is noncanon, just a fairytale people in-universe tell"
"This 1 scene in Chi is canon, disregard the rest"
"Also the game is now called Unchained X"
"The whole damn thing is canon afterall"
"Also the game is now called Union X, with X being a different word than before"
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"Namine & Roxas have a close relationship & are together in spirit at the end of KH2"
"No they don't, Roxas barely knows her & cares more for his sister-clone who wasn't even hinted at in KH2"
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"Kingdom Hearts is the only way to reach the Realm of Darkness, Riku & Mickey are trapped"
"Actually they can just enter & leave whenever they feel like it"
"Also that wasn't the real Kingdom Hearts"
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"Organization XIII's purpose is create a KH that gives them their hearts back"
No, it's actually pretty easy to get their hearts back & their real goal is form the X-Blade"
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"This other bad guy is Xigbar/Braig"
"Wrong again, it's Luxu"
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"Maleficent was destroyed & can't come back (as said in CoM)"
"Actually Maleficent did come back to life"
"Actually she wasn't dead, but sent back in time because getting clubbed to death does that I guess"
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"Emblem heartless were created 10 years ago"
"Actually emblem heartless exist 75 years ago due to lazy asset flipping & Dark Road hasn't even explained it yet"
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"Time travel is as easy as a magic door & can totally alter history (Timeless River)"
"Actually time travel requires these very specific steps & can't change history"
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I'm sure more will come to mind later, but I don't get why this series can't go 1 game without pulling a "you thought you knew but you were wrong" twist. Just tell a new story, a new adventure & leave the past alone already. At this rate the next game will reveal that Baldr & Pence were secretly roommates in collage.