Real Organization XIII

The second Organization XIII is a group consisting of thirteen different incarnations of Master Xehanort that debuts in Kingdom Hearts 3D: Dream Drop Distance. It was first mentioned by Yen Sid in Signs of What's Next when he claims that one Keyblade Master will not be enough to counter what is not "a single one of Xehanort".

History
The true purpose of the original Organization XIII led by Xemnas was for each of the Nobody members to host a fragment of Master Xehanort's heart, turning them into clones of Xehanort, but the members' unforeseen independence made this goal impossible to realize.

However, in anticipation of this failure, Master Xehanort had arranged for Young Xehanort to be sent by Ansem, Seeker of Darkness to travel to different periods of time and gather different incarnations of Xehanort, who would be added to the ranks of a new Organization. Young Xehanort succeeds in filling twelve of the Organization's seats, and he and the revived Master Xehanort attempt to make Sora into the final vessel. When Sora is rescued by Riku, Mickey, and company, Master Xehanort is forced to flee with his incomplete Organization.

Later on, Yen Sid says that the thirteenth member has been found.

Members
Master Xehanort: The original Xehanort. He is the leader of the second Organization XIII.

Young Xehanort: The younger version of Xehanort who traveled through time with the assistance of Ansem.

Ansem, Seeker of Darkness: Terra-Xehanort's Heartless.

Xemnas: The leader of the previous Organization XIII, and Terra-Xehanort's Nobody.

Xigbar: The Nobody of Braig who was part of the original Organization XIII alongside Xemnas. He claims to be "half-Xehanort".

Isa: Lea's childhood friend turned enemy, and the original, whole entity of Saïx, who was previously a member of the first Organization XIII.