Scala ad Caelum was not a topic he discussed often. It was not, in truth, a topic he tended to discuss at all, because who would he discuss it with, when his many selves already knew all there was to know, or all they had ever wanted to know, and the others... well. Xehanort had never been fond of offering weakness, or sentiment, that could be used against him.
"They died, some very few retired." Was his answer, matter-of-fact and only carrying the barest shadow of exhaustion.
And yet, as Kairi picked up the pace, and Xehanort chose the branch of the path he felt more confident about, he considered her questions. Nodded, of course: he had known Yen Sid, that was exactly what he had implied.
"We were not close friends, there was perhaps a year or two between us, and we did not train under the same Master. But with only a handful of Wielders when I became a Master," he told Kairi, his amusement somewhat rueful, "of course we knew each other."
And it had not been the danger it was now, in a way.
"We were scholars, both of us." He revealed. "I respected him, and I believe it was mutual, and we tended to butt heads, as two of the youngest Masters."
It felt like more than a lifetime ago.
"We had too much in common to truly become good friends, when I could hardly stand to remain in Scala ad Caelum for long." He shrugged, with just one shoulder. "Now... well. We are enemies."
But they had been close in age, and in experience.
"He's grown callous, with age." And then, after a moment, regarding Kairi, "I kept expecting him to intervene during Sora's Mark of Mastery. It was his duty, to do so."
He'd been told he would not, but the youth he knew... well, he'd believed he would.