I apologize ahead of time if there's another thread like this, but I just want to someone to please answer my question if they can: In the event when Master Xehanort released his heart from his body using his keyblade, a nobody should have been formed right? Also in the last episode when Aqua defeats Terra-Xehanort, Terra-Xehanort points his keyblade to unlock his heart again. In the event that happened was something else created like another nobody when that occured?

Well, I believe the second time, he was locking his heart, not actually freeing it or anything...

Thats a good question, but maybe a heartless needs to take you're heart, but then again that wouldn't explain sora's deal, maaybe it was due to his body was about to die, and it died the moment he released the heart, and with Terra-nort, maybe he was just trying to get into the dark realm, cause he didn't faid like xehanort.

well the first time when he released his heart i'm not sure but the second time Terra locked the memories in his heart so xehanort lost his memory and could not remember the ability of wielding a keyblade.

His heart went into Terra during the first time, so a nobody didn't create during that period of time. But when he released his heart the second time, I think his "Guardian" was destroyed