Wong Leung

Wong Leung was the martial artist responsible for adopting and training Sion Barzahd, who he found wandering the streets as a young man. He also passed his knowledge of martial arts on to Dauragon C. Mikado, but he took it upon himself to stop his former pupil when he learned what Dauragon planned to do with his weaponized satellite. Dauragon, however, had become a better fighter than his mentor and fatally wounded him during their duel. With his dying breath, Wong asked Sion to forgive him and urged him to stop Dauragon.

The Bouncer trilogy
Although he was killed by Dauragon's vicious hands, Ayame did want to keep a promise to Sion; after she revealed about the Dragon Balls, she wanted to wish back his master after they save the world and Dominique from the CEO. When they did, Ayame gathered the elusive Dragon Ball with the other seven and wished back all the people Dauragon had destroyed, excepting Master Mikado, Kaldea, and Mugetsu. Later on during Sion's shift at Fate, he had a short dream where he was at the woods training with Wong one last time and learning the lesson on becoming stronger while opening his heart to others.

A few weeks later, Sion's wish was fulfilled as he saw Wong at the Capsule Corp. while Dominique's operation was ending. He congratulated the young Z-Fighters for their courage and a job well done.

He was seen several months later during Sion's 20th birthday, especially witnessing his transformation after having several drinks of Sapporo awakening his darker side. Wong was shocked of this, even his sinister behavior. Then he was ambushed by a street gang before Sion raged on them and released his inner darkness via fission. He then invited Sion to his childhood place, away from Edge, while his propaganda was mounting. He then taught Sion the process of meditation and combatting his inner demons, while Ayame taught him the Kamehameha Wave, to which Wong himself knew from Master Gohan and Roshi; the latter he didn't like much just as Ayame doesn't.

Sion then left a farewell letter to him, honoring his death if the worst should happen while he pursues his darkness and saves Dominique. Lastly, Sion was successful and Wong decided to settle with him at his past home, restarting his brighter future.