Battle (Member) again, but be warned—
(s)he's stronger than before.
Before challenging a Replica Data
The Organization XIII Replica Data (XIII機関：再現データ Jūsan Kikan: Saigen Dēta?, lit. "Organization XIII: Replica Data") are digital replicas of Organization XIII’s members, minus Xion, who appear as optional bosses in Kingdom Hearts II Final Mix.
The Replica Data dwell in the Garden of Assemblage at the end of the Cavern of Remembrance in Radiant Garden. To navigate the entire cavern, Sora will require the Growth Abilities from his Valor, Wisdom, Master, and Final Drive Forms, all of which must be at least Level 3. This means that Sora must reach The World That Never Was and defeat Roxas at Memory's Skyscraper before he can reach the Garden.
Once the player reaches the Garden of Assemblage and activates the computer within, they will be able to fight against replicas of Xaldin, Axel, and Demyx. Once the player completes the game, they will also be able to fight the replicas of Xemnas, Xigbar, Saïx, Luxord, and Roxas. In order to unlock the replicas of Vexen, Lexaeus, Zexion, Marluxia, and Larxene, the player must defeat their Absent Silhouettes; they can do this either before or after clearing the game.
The data replicas are much, much stronger than the original members: They possess a higher damage output, increased HP, and all of them have different attack patterns and properties so as to force the player to relearn strategies, making them the hardest opponents in the game besides the Lingering Will. The player can rematch them as many times as they desire, and defeating each yields its own reward, but Sora gains no experience from fighting them. The terminals that hold the data of each individual member glow blue at first, but turn red once the player defeats the member within for the first time. After Sora defeats all thirteen replicas, a treasure chest will appear beside the computer, which holds the Proof of Nonexistence.
The Superior of the In-Between is the only Replica that Sora fights twice, first alone at Memory's Contortion, and then in the Realm of Nothingness with Riku by his side. Between the two battles, the player has the luxury of access to the menu, but if the player fails to defeat Xemnas's second form, they must start the entire fight over. Defeating Xemnas will reward a Power Boost, and he is the only one among the thirteen to grant it.
The Freeshooter fights Sora, Donald, and Goofy in the Hall of Empty Melodies in The World That Never Was. Defeating him will reward a Defense Boost.
The Whirlwind Lancer fights Sora, Donald, and Goofy at the Bridge of Beast's Castle. Defeating him will reward a Defense Boost.
The Chilly Academic fights Sora, Donald, and Goofy at the gate of the Old Mansion in Twilight Town. Defeating him will reward a Lost Illusion.
The Silent Hero fights Sora, Donald, and Goofy at the Station of Remembrance, an isolated arena reminiscent of Castle Oblivion. Defeating him will reward a Lost Illusion.
The Cloaked Schemer fights Sora, Donald, and Goofy at the last remnants of Destiny Islands before darkness consumed the world. Defeating him will reward a Lost Illusion.
The Luna Diviner fights Sora, Donald, and Goofy at the Addled Impasse in The World That Never Was. Defeating him will reward a Defense Boost.
The Flurry of Dancing Flames fights Sora alone in the basement of the Old Mansion in Twilight Town, where he last fought Roxas. Defeating him will reward a Magic Boost.
The Melodious Nocturne fights Sora, Donald, and Goofy at the Castle Gate of Radiant Garden. Defeating him will reward an AP Boost.
The Gambler of Fate fights Sora alone at Havoc's Divide in The World That Never Was. Defeating him will reward an AP Boost.
The Graceful Assassin fights Sora, Donald, and Goofy at the Station of Oblivion, the room in Castle Oblivion where he met his end. Defeating him will reward a Lost Illusion.
The Savage Nymph fights Sora, Donald, and Goofy at he Station of Remembrance, an isolated arena reminiscent of Castle Oblivion. Defeating her will reward a Lost Illusion.
The Key of Destiny fights Sora alone at Sora's Station of Awakening. Defeating him will reward a Magic Boost.
Each door leading into one of the data fights contains a floating outline of each of the Organization members' weapons, with the exception of Xemnas, who uses his Dragon Form's shield, despite this form not being present as a data fight.