This one is from the end of KH II novel volume III. In other words: Xemnas vs. Rikunort.
Namine was silently crying as she sat in her chair.
In the white room of the haunted mansion, the pictures that Namine had drawn were hung on the walls. While waiting for Axel and Riku, Namine had passed the time drawing alone in this mansion. Riku glanced about the room at the many pictures that he hadn’t seen before.
However, when Riku saw Axel, himself, and Namine’s smiles drawn there, he turned his gaze away.
Then, Riku felt that outside the mansion their enemies were moving.
“Namine, return to the basement now. Hide in the pod room.”
Riku said as he placed his hand on Namine’s head, looking out the window.
Come to think of it, the last time this mansion was attacked by nobodies was when Axel attacked it. But it wasn’t this mansion; it was another place with the same form as this mansion.
“Riku, do you think Nobodies have a place to return to?”
“We don’t have time now. When the Organization is attacking, I don’t know if I can protect you and fight at the same time.”
Soul Eater was gripped in Riku’s hand.
“I can only say it now. Do you think Nobodies really don’t have hearts? Who told Axel that he doesn’t have a heart? Hearts…the secret of hearts…”
“Namine!”
Riku cut off Namine’s words with a shout—and then from the corners of the room Nobodies appeared. The Nobodies made a giant leap and swooped at Namine. With barely any room to spare, Riku rushed between the Nobodies and Namine and pushed the Nobodies back with Soul Eater.
“So you were here.”
The space inside the room shifted and the form of a black coated man appeared. Standing protectively before Namine, Riku readied his Soul Eater.
“It’s been a long time since I’ve seen that face.”
The man took his hood off and smiled at Riku.
Two faces, both nearly identical, confronted each other.
The man standing there was Xemnas.
“You’re Xemnas.”
I didn’t think that Xemnas would really come here.
If I believe what Axel said, I can’t win against Xemnas on my own.
Even so, I can’t just give up hope.
At least if Namine can get away—
“That’s right. Riku—No, Ansem…but it’s not Ansem either. I should call you Xehanort.”
Xemnas silently walked toward Riku.
“How is it? That body is quite good, isn’t it?”
“It’s the worst.”
Xemnas chuckled at Riku’s words.
“That will do. Now, let’s go!”
In Xemnas’s hand a sword glowing with red light—the Aerial Blade—appeared.
Then Soul Eater and Aerial Blade crashed against each other.