A boy who is closely tied to Sora and wields a Keyblade. Introduced in Kingdom Hearts II as a seemingly ordinary teen enjoying his last days of summer vacation in Twilight Town, he is eventually revealed to be Sora's Nobody and the thirteenth member of Organization XIII, the "Key of Destiny", who defected in order to reunite with Sora and put an end to the Organization's plans.
- Anti-Villain: He's the variety of being the Token Good Teammate of an ambiguously villainous organization.
- Cool Sword: He's a Keyblade bearer and gets all the perks that come with it. He later gains the power to whip out two at once.
- Defector from Decadence: As shown in 358/2 Days, he became so fed up with the Organization (Axel included) keeping secrets about himself and Xion from him that he left to find answers on his own.
- Dual Wielding: He gains the ability to wield two Keyblades at once after defecting from the Organization. According to Birth by Sleep Ultimania, the second Keyblade is actually Ventus'.
- Et Tu, Brute?: Axel winds up discovering Xion's true identity before Roxas, but keeps it a secret from him and allows her to leave the Organization. Roxas is furious when he finds out and virtually terminates their friendship because of it.
- Hair of Gold, Heart of Gold: The whole "heart" thing has been debated since he's a Nobody, but he's an unarguably friendly kid who manages to make many friends.
- Holy Hand Grenade: His element in the Organization is "light", or in other words, creating destructive pillars of light
- Morality Pet:
- Yin-Yang Bomb: His two Keyblades come attached with the Oathkeeper and Oblivion keychains while Dual Wielding, symbolizing light and dark as much as Sora's connection to Kairi and Riku, respectively.
Organization XIII's eighth member, the "Flurry of Dancing Flames", formerly named Lea. He manipulates the element of fire, and wields a pair of chakrams as his weapons. Axel is one of the members Sora encounters in Chain of Memories, where he is tasked with weeding out the traitors in the Organization stationed at Castle Oblivion. However, later games flesh out more of his character, such as his friendship with Roxas.
For information on Lea, Axel's Other, see Kingdom Hearts: Supporting Originals.
- Anime Hair: Has a mass of spiky red hair. It's a wonder how it fits under his hood.
- Back for the Dead: After disappearing halfway through Kingdom Hearts II, he returns just before the climax to perform a Heroic Sacrifice that allows Sora and co. passage to the World That Never Was.
- Back from the Dead: His death at the end of Kingdom Hearts II, coupled with the destruction of his Heartless, results in his human self being restored with all of his memories as a Nobody intact in Dream Drop Distance.
- Becoming the Mask: Reading the secret reports in 358/2 Days reveals that Axel's initial promise of friendship to Roxas was a lie and that he didn't really feel anything toward him, since Nobodies have no hearts. After coming back from the events at Castle Oblivion, however, he gradually becomes Roxas's friend for real. It's all but stated in Dream Drop Distance that this was made possible as a result of his contact with Sora's heart, which caused him to develop a new heart for himself.
- Big Brother Instinct: In regards to Roxas, this is his driving motivation between 358/2 Days and Kingdom Hearts II after he started mentoring Roxas. Of course, a lot of this has more to do with himself than with Roxas until toward the end.
- Breakout Character: He wound up getting an extended role in Kingdom Hearts II after his role in Chain of Memories was popularly received, and was made one of the main characters in 358/2 Days.
- Catchphrase: "Got it memorized?"
- Character Development: When introduced, Axel is a remorseless assassin who kills his own comrades without batting an eye, and dismisses any emotions he feels as his own thoughts playing tricks on him. However, his friendship with Roxas and Xion causes him to develop more human-like behavior, which culminates with him trying to bring Roxas back after his convergence with Sora, stating that Roxas was the only one who made him feel like he had a heart.
- Demoted to Extra: His role is reduced between Chain of Memories and Kingdom Hearts II
- Facial Markings: He is distinguished from his human form as having triangular marking under his eyes.
- Flash Step: He will warp just in time to catch the chakram he throws.
- I Will Find You: His primary motivation in Kingdom Hearts II is to reunite with his friend Roxas, who by then has left the Organization and merged with Sora. This is stemmed from The Promise he makes in 358/2 Days to bring Roxas and Xion back every time they try to run away.
- Kick the Dog: In Chain of Memories, he threatens to kill Naminé when Marluxia uses her as a shield. He later pushes the Riku Replica off the slippery slope with an empty promise to make him into the real Riku by setting him on Zexion.
- Kick the Son of a Bitch: He eliminates Vexen and Zexion, two of the Organization's resident Insufferable Geniuses who pleasure themselves with tormenting Sora and Riku. The former was done in order to gain Marluxia's trust, while the latter was because he knew too much about what happened at Castle Oblivion.
- Playing with Fire: As a fire specialist, he wreathes his chakrams in flames and throws them at his opponents like fireballs. He also creates a Ring of Fire as a sleight in Chain of Memories, and during Roxas' boss fight against him in Kingdom Hearts II.
- Poisonous Friend: As demonstrated in 358/2 Days, he's so obsessed with keeping Roxas and Xion as his friends that he lies to them, does questionable stuff behind their backs, and when they try to leave the Organization of their own free will, he attempts to bring them back by force for selfish reasons. Roxas does wise up near the end and responds in kind by leaving for good. Axel eventually redeems himself in Kingdom Hearts II by sacrificing himself to save Sora and, in turn, Roxas.
- Precision-Guided Boomerang: His chakrams will always return to his hands when thrown, no matter what direction.
- Promoted to Playable: Along with the rest of Organization XIII, who appear as bosses in Chain of Memories and Kingdom Hearts II, Axel is a playable character in 358/2 Days' Mission Mode.
- Rings of Death: His chakrams, the Eternal Flames.
- We Used to Be Friends: Prior to Kingdom Hearts II, he and Roxas suffered a falling out that partially fueled the latter's desire to leave the Organization. By the time they meet again at the start of the game, Roxas has had all of his memories overwritten by DiZ, which upsets Axel so deeply that by the time Roxas regains his memory, Axel declares that he's "too late" and carries out his order to eliminate his friend. They're able to reconcile at the end, though, and share one last sea-salt ice cream together in a dream after Axel's death.
The mysterious fourteenth member of Organization XIII, joining one week after Roxas. She bears an uncanny resemblance to Kairi, and wields a Keyblade of her own. Her existence is chronicled in 358/2 Days, where she is shown to be friends with Roxas and Axel during their time together in the Organization—before the tragic truth of her identity is brought to light.