Rugal Berstein is a vicious fighter & arms dealer who lives on his personal aircraft carrier, Dark Noah. He is prone to encasing his defeated opponents in liquid metal and displaying them as trophys. Rugal has a brother that he use to work with but the split up over conflicting interests.
When Rugal was 25 years old he encountered an 18 year old Leopold Goenitz. The two fought but Rugal lost the fight and his right eye. Impressed that Rugal survived the encounter Goenitz bestowed a portion of the Orochi power upon him. Goenitz secretly ordered Mature & Vice, two member of the Hakkesshu, to watch over Rugal and the two went to work as his secretaries. The duo helped arrange the 1994 and 1995 King of Fighters tournements.
In 1994 when Team Japan made it to the finals Kyo Kusanagi discovered his father defeated and almost lifeless. With the help of teammates Goro Daimon & Benimaru Nikiado , Kyo defeats Rugal. Not wanting to live with the shame of defeate, Rugal detonated the aircraft carrier they were on. Team Japan maanged to escape and Rugal survived but lost his right forearm.
Returning in 1995, Rugal would again come face to face with Team Japan. This time, Saisyu Kusanagi, Kyo's father, was brainwashed into fighting besides Rugal. Upon his defeate, he was freed of Rugal's influence. Team Japan once again defeated Rugal but this time Rugal tried to tap into the Orochi power and it consumed him as he was not a blood member of the Hakkesshu.