Axel's element is Fire, and uses his duel chakram in combintion with his fire.
History:
[SPOILER - highlight to read]: Axel pretends to join with Larxene and Marluxia in their plan to seize control of the Organization using Sora. To gain their trust, he assassinates Vexen when ordered by Marluxia to rid them of "traitors".[11][14] Afterwards, to derail Marluxia's plans, Axel sets Naminé free so that she can reveal to Sora the truth about how she manipulated his memory.
Eventually, Axel confronts Marluxia, prepared to destroy him. Marluxia uses Naminé as a shield to keep Axel at bay, though Axel resolves to go through anyone, even Naminé. When Sora makes a sudden appearance, Marluxia vanishes with Naminé, leaving Sora to fight Axel. Sora defeats Axel, after which he states the existence of their relation before vanishing, letting Sora believe him to be gone for good. After Marluxia is defeated by Sora, Axel enlists the aid of the Riku Replica that Vexen created to get rid of Zexion in Castle Oblivion's basement levels.
In Kingdom Hearts II, Axel attempts to rescue Roxas from DiZ's virtual Twilight Town. Despite Axel's efforts, Roxas merges with Sora. Later, acting separately from the Organization, Axel kidnaps Kairi to bait Sora to him. However, Saïx takes her away so the Organization can use her to fuel Sora's anger. During a visit to Twilight Town, Saïx warns Sora that Axel desires to turn him into a Heartless. Axel appears after the Heartless invasion of Hollow Bastion to Sora, and informs him that Organization XIII has been using him to get hearts. He then apologizes for getting Kairi involved. Before he elaborates, Saїx appears and Axel promptly flees.
Axel finds Sora in a pathway to the World That Never Was and chooses to fight Nobodies with him. The numbers get overwhelming and Axel performs a kamikaze attack to save Sora. Fading away, Axel apologizes for kidnapping Kairi and asks Sora to rescue her. When asked what he was trying to do, Axel admits he wanted to see Roxas, who made him feel like he had a heart, and Sora made him feel the same way. With the last of his strength, Axel opens an entrance to the World That Never Was.
Quote, Axel's last words "Sorry? my heart just wouldn't be in it, you know?"
One of Axel's goals was to turn Sora into a Heartless so he could get Roxas back
Attack abilities
Axel Combines fire with his chakrams, he fights in melee with his weapons as well as throwing them at a very high speeds. He is total unharmed by fire as he can also hide in it. He can turn a battle field into a raging inferno, create fire gysers asnd launch fire at enemies in a variety of ways