"A girl who uses the Keyblade for the Organization. Her powers over light blind and confuse enemies.
She joined the Organization in Kingdom Hearts 358/2 Days (2009)." - Johnny's Journal
Johnny first meets Xion when Johnny fakes becoming a Nobody. Becoming Honjynx, Johnny slowly adapts to spying on the Organization by becoming one of them. However, during one of his missions with Xion, she tells him that no one found out about him a month ago. Johnny realizes that Xion can be trusted and begins his friendship with her. After another mission together, Xion brings Johnny to the Clock Tower. He becomes friends with Roxas and Axel.
However, once Johnny's plan is revealed, Xion does not fight alongside the Organization as they attempt to kill Johnny. He thanks her for not lifting her blade. Xion smiles and says that's what friends do.
When Johnny comes to the Organization for help against Jonathan's forces, Xion is one of the few who stands up for him. When he later goes to fight Jonathan, she leads the Organization to Johnny's side. She is later seen fighting alongside Kairi.
Xion is also one of Johnny's memories during the final battle between Johnny and Jonathan. When called into battle, she casts Faith, damaging Jonathan and healing Johnny.
Xion is classified as a White Mage, using her powers over light to cast spells to protect the party and confuse enemies. Unlike most White Mages, Xion is skilled in combat.
Xion's personal Limit Break is Event Horizon, where her Keyblade takes on an aura of light and attacks her opponent consantly. She ends the Limit by sending out Light shields that home in on the enemy. More light shields are produced the more you charge the Limit.
- Unlike 358/2 Days, Xion is not a clone of Roxas, as Roxas uses a more distinct fighting style including the new art of Keyblade Fusion.