Tung Fu Rue/Story

Past
The legendary master of Hakkyokuseiken, Tung Fu Rue was the former master of both the noble Jeff Bogard and the power hungry Geese Howard. Although he had trained both men, he wanted Jeff to be his only successor since he displayed proper decorum for a honorable fighter. Geese caught wind of this and murdered Jeff out of jealousy. Tung was saddened by the loss and dropped the idea of adopting a successor. Tung had entered the 1992 edition of The King of Fighters tournament held by Geese, but was eventually defeated.

In his ending for Fatal Fury Special, he seems to have overexerted himself and is hospitalized. This scene is most likely a callback to the first OVA since he is fine throughout the rest of the series. He decides to live the rest of his days in retirement and he occasionally enters a competition to keep in shape. Though he taught Terry for a time, Tung made it a policy to refuse any other disciples. He seems to break this in Real Bout by apparently making the Jin brothers his apprentices. Some endings in Real Bout 2 show him taking only Jin Chonrei as his apprentice though, with Jin Chonshu staying with Kim Kaphwan.

The King of Fighters XIV
He's established to have connections with Saisyu Kusanagi and Chin Gentsai in this series. Before The King of Fighters XIV, Tung found the orphan Shun'ei. Sensing good in the boy, Tung raised Shun'ei as one of his last disciples alongside Meitenkun. In truth behind Shun’ei’s adoption by Tung, at time after the boy suddenly becomes a wielder of multiverse-based powers Amplified Specters, and almost destroy his neighborhood and his family’s normal life while feeling lifeless, the old master himself was entrusted by Shun’s parent before tearfully bid their son a permanent farewell, and enlisted Tung to lie to Shun about how he was adopted by Tung after his soul became clear and normal. However, when Shun’ei suddenly have a recurring nightmare of being haunted by a malevolent voice relating to his Amp power, Tung gave him his headset, in addition to the music players to keep his mentality to control the Amp in check and calm down.

The King of Fighters XV
As Tung retires from tournament, despite his first participation, he originally wanted to enlist Kyo to look after Shun’ei and Meiten. However, due to Kyo’s hand are full because of a distortion within Orochi’s seal caused by Otoma=Raga (the same being behind Verse incident in the previous tournament) is suddenly broken and have no choice to form Team Sacred Treasures as a regular team in fifteenth tournament, he entrust Benimaru Nikaido to take over the spot as a third member of Shun’ei’s team.

After Shun’ei and the rest of presenting main teams (other members from his team, Team Sacred Treasured, Team Isla, and Team Ash) defeated Otoma=Raga and save the multiverse at the same time where Shun’ei becomes cured, Tung finally explains to Shun on how the boy was truly adopted after his Amp was awakened and left by his parents under Tung’s care.