Before Kingdom Hearts III
During his time with Organization XIII, Vexen created twenty replicas as part of his research. While two of these replicas—Riku Replica and No. i—went on to become successful in their own right, and the six that followed would come to be used as vessels for the real Organization XIII members who traveled through time, the initial twelve were deemed as failures, barely considered to be human at all.
Kingdom Hearts III
As part of Xehanort's final plan, Vexen is recruited to refine the initial twelve replicas to make them closer to real humans, which are converted into the Replica Xehanorts. The completed replicas appear in Scala ad Caelum, having been summoned by Master Xehanort. Initially appearing as phantoms of the original Xehanort, they soon take on a new form, wearing purple cloaks with silver masks hiding their faces. The twelve replicas vanish, hiding in four smaller groups for surprise attacks. After being defeated by the trio, the replicas are absorbed by Master Xehanort to increase his powers, transforming him into Armored Xehanort.
After Sora manages to break his armor, Master Xehanort releases the Replica Xehanorts to battle the Guardians of Light at the Keyblade Graveyard. The Replicas manage to trap Lea, Roxas, Xion, Aqua, Terra, Ventus, and Riku in a dark void, leaving a weakened Mickey to fight them. With future Sora lending aid, Mickey temporarily disperses the replicas and pulls everyone out of the darkness.
Following Master Xehanort's desire to keep the pure light away from the Guardians, the replicas return once more, this time merging into a copy of Armored Xehanort. The Armored Xehanort faces off with Sora, who restored Kairi with the power of waking. Sora and Kairi fight the combined replicas, and they are finished off by a combined attack from all of the Guardians of Light.
The Replica Xehanorts wear a black suit of armor with red outlines and a black and silver mask with spikes. Their greaves are silver with red outlines, and their gauntlets are red and serrated. Their boots are silver and red with high heels. Over this suit of armor they wear a dark purple tunic decorated with red and two black belts around their waist.
The Replica Xehanorts each use the abilities and signature weapons of one of the members of the real Organization XIII, aside from Master Xehanort himself. The replica of Ansem also does not wield a weapon, rather relying on Ansem's dark powers. All the weapons have a blue glow that obscures most of their features. While they appear in groups of three-to-four, the replicas tend to attack one at a time, while the others hang back. Should one replica be countered or attacked, another will use the opportunity to attack Sora. Each group has a replica with long distance attacks, be it Fair Game, Foudre, Sharpshooter or Ansem's dark powers. Marluxia's replica can also make surprise attacks from behind, dealing damage with a horizontal spinning scythe attack. In order to avoid Sora, they rely on teleportation and quick attacks, often "tagging out" with other replicas to confuse Sora.
When fighting the Guardians of Light at the Keyblade Graveyard, the Replica Xehanorts all wield the No Name Keyblade. They merge together into Armored Xehanort in order to fight Sora and Kairi and retain all of their Keyblade from their previous unfused state, as Armored Xehanort they utilize the attacks that Master Xehanort used during his time as Armored Xehanort.
Notes and references