 Six members of the Organization serve as the antagonists of the game , though only four appear in Sora 's story mode , while the rest appear in Riku 's story mode . Among the four are Marluxia , the antagonist and lord of Castle Oblivion ; Larxene , a female member assisting Marluxia ; Axel , a double agent whose loyalties are hidden ; and Vexen , an unwilling participant in Marluxia 's plan . Zexion and Lexaeus , allies of Vexen , appear only in Riku 's story mode . Ansem also appears in Riku 's story as an entity within Riku trying to gain control of him . Many of the Disney villains return ; although they are memory @-@ based recreations like the rest of the Disney characters , they have different motivations compared to their Kingdom Hearts counterparts . 
