How is it possible that he can only be fought after sealing Keyholes and defeating Xemnas? There are no keyholes in KHII, and killing Xemnas ends the game.

  • sigh!*..... Ok, 1-Yes, there are Keyholes. I'm not sure how else to explain it to you.

2-there's anoption at the end of final mix that lets you returrn to the game after Xemnas is defeated. -xNaminéx

Technically they're not keyholes, they're loopholes in the Gummi shield around each world...or something like that.—Urutapu 23:55, 24 March 2009 (UTC)
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KrytenKoro - "It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
TALK -
I've never understood that - it's so incredibly important in KH to seal those keyholes to save the universe, while in KH2 they're all "Open them up! What's the worst that could happen?"

If I understand correctly, the game lets you save the fact that you have beaten Xemnas, though it still places you, story-line wise, right before the boss, like in Chain of Memories.