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It became what we know as Xehanort, fan-nicknamed as Terra-nort, the man who became Ansem the wise's apprentice and then turned himself into an heartless. The heartless took the name Ansem, seeker of Darkness and the leftover body became Xemnas, the nobody leader of Organization XIII. It is not clear (as far as I know, at least) however if Old Xehanort actually had full contol over the body or if the new Terra-nort had a personality of his own, as he was found without memory after the fight with Aqua. AkaAxl 15:58, April 9, 2013 (UTC)