Take the tour ×  When does Xehanort 'Terra-Xehanort / Ansem',
split into Xemnas and Ansem the Nobody? Why does he do this?
Does this happen at the end of Birth By Sleep? Or is this
something that is going to be explained in KH:3D?  share|improve
this question add comment  1 Answer  It happens in the time
between birth by sleep and Kingdom Hearts, when Xehanort is
apprentice to Ansem the Wise. Throughout the series, it is
implied and accepted that his heart succumbed to darkness. No
details of this occurrence are even shown in cutscenes.  That
is, until Kingdom Hearts 3D. In the opening scene, Apprentice
Xehanort is shown extracting Braig's heart manually via Master
Xehanort's keyblade, so this may imply that he did this to
himself as well.  share|improve this answer add comment  Your
Answer