The siblings reside on an airship called "Sky Noah". In The King of Fighters 2003, he would challenge fighters there at the behest of his sister. His story in The King of Fighters XI implies that he faced the Ikari Warriors Team and was defeated by them. He peacefully chats with Heidern and explains that he is only following his father's legacy. In his ending for the game, he seems to appear regretful for his actions and yells at his sister for insulting his opponents.
The Console Edition of The King of Fighters XIII reveals more of Adel's cooperation with Heidern (in which he addresses him as "Colonel Heidern") as he tries to help the forces of good suppress the evil plans of Those from the Past. When Rose is finally freed, he reassures his sister he would punish those responsible for her subjugation.
His style is very similar to his father Rugal's. Unlike his father, his moves are faster and is also easier to chain. On the other hand, his moves are significantly weaker in priority.
