Marluxia

From Kingdom Hearts - Wiki on Neoseeker

Using the power of nature and a scythe to fight Marluxia is the main antagonist in Kingdom Hearts: Chain Of Memories. Leading Sora, Donald, and Goofy to Castle Oblivion he is the one who explains the use of cards and how their memories will be effected within the Castle.

In the beginning of the game Marluxia tells Sora that someone precious awaits him at the top without telling him who it is, but in order to reach the person he'll have to sacrifice his memories. While Sora makes his way through the castle he encounters multiple people in the Organization helping Marluxia with his plot. Marluxia is planning to rebel against the Organization's superior by trying to manipulate Sora therefore having the power of the keyblade master. Three fellow Organization members appear to be helping Marluxia, Larxene, Axel, and Vexen. Using his fellow members to help manipulate Sora he tells them to confront Sora before he does, and uses Vexen's Riku Replica to confuse Sora. While Sora continues to get closer to the top of Castle Oblivion he continues to lose his memories which is revealed to be the work of Namine. Marluxia had captured Namine so he could use her to replace Sora's memories to lure him to the top of the castle. When Sora is on the Twilight Town floor Marluxia blackmails Vexen ordering him to kill Sora, and after Vexen had left orders Axel to kill Vexen before he kills Sora. On the top floor Axel betrays Marluxia and attempts to kill him even willing to go through Naminé to do it only to be stopped by Sora. Sora then confronts Marluxia and defeats him only to have revealed that what he defeated was a Marluxia Replica and the actual Marluxia is through a door into a weird realm. Sora then fights and kills the actual Marluxia.