Organization XIII's Replica Data
An Organization XIII's Replica Data (XIII機関：再現データ, Jūsan Kikan: Saigen Dēta?, lit. "Organization XIII: Replica Data") is an optional boss fight found in Kingdom Hearts II Final Mix at the Garden of Assemblage. Once Sora, Donald Duck, and Goofy reach the Garden of Assemblage, they can access a computer that reveals portals corresponding to each defeated Organization member. The portals are labeled with their member's signature weapon and are arranged in the same manner as the thrones in Where Nothing Gathers. When used, a portal will transport Sora and his friends to a digital copy of the arena in which the member was defeated, where the battle will take place. In order for a portal to be operational, the episode or mission containing the final battle with its corresponding Organization member or Absent Silhouette must have been completed. Once a replica is defeated, it simply decodes until the next time it is challenged. While the battles are extremely difficult, with enhanced stats and attacks far beyond those of their real counterparts, they are the most efficient way of farming Stat Boosts and Lost Illusions. Defeating all thirteen members will cause a chest containing the Proof of Nonexistence to appear.
Similar to the gravestones in the Proof of Existence, the doors leading to the Organization XIII's Replica Data in the Garden of Assemblage display a silhouette of each member's weapon. The only exception is Xemnas, whose door displays the shield used by his Dragon Form.