Rugal Bernstein was the boss fighter in SNK Playmore's early King of Fighters fighting game series.

According to his official biography, Rugal was born on February 10, with no place or year specified. He stood 1.97 m (6 ft 4 in) and weighed 103 kg (227 lb). His blood type was unknown. His hobby was "resurrection." He had no favourite food (claimed he'd eat anything) or sport (claimed he's good at everything). His most valuable possession was his own evil soul, and he hated anything that got in his way, including justice. His fighting style was an amalgam of various arts, including Hakkyokusaken and House of Strolheim, the styles used by Geese Howard and Wolfgang Krauser .

The details of Rugal's early life are unknown, but by the events of The King of Fighters, Rugal has become an international arms dealer, operating out of his aircraft carrier Blacknoah, accompanied by servants and his pet panther, Rodem. Not only was Rugal feared in international politics, but also in the fighting world; he was a vicious combatant, Rugal took his defeated foes and dipped them in liquid metal, making them into grisly statues to commemorate his battles.

Heidern , a mercenary leader, had been trying to infiltrate Rugal's operation, so Rugal kidnapped his wife and daughter, daring him to try and mount a rescue. When Heidern brought an entire company to the Blacknoah, Rugal - on his own - wiped them out to a man, and would have killed Heidern if his family had not interfered; instead, he killed them and left Heidern with one eye and grievous injuries.

Rugal later sensed a tremendous power in the middle of nowhere, and when he went to take it, Goenitz appeared, took out his eye with one strike, and gave him a small portion of the power of Orochi for surviving the attack. Returning to the Blacknoah, Rugal had a bionic eye implanted, and recruited two secretaries: Mature and Vice. With their help, Rugal organized a King of Fighters tournament, in order to find worthy opponents. During the invitation phase, Saisyu Kusanagi came to the Blacknoah and challenged Rugal. Although Rugal won, he did not subject him to the metal bath. When Saisyu's son, Kyo, arrived with his teammates, Rugal had Saisyu fight his own kin. However, Kyo defeated Saisyu. Unwilling to accept defeat, Rugal blew up his ship.

Rugal was believed dead, but he used the Orochi power to survive. Replacing his destroyed right forearm with cybernetics, Rugal revived Saisyu, brainwashed him, and sent out invitations the following year for another King of Fighters tournament. Rugal used an abandoned missile silo as his base in 1995, and abducted the winning team (again, Kyo's team) to fight Saisyu, and then himself. Despite using the Orochi power and becoming "Omega Rugal," Kyo's determination saw him though. Again defeated, Rugal tried to use more of the Orochi power, but it consumed him. As his body disintegrated, he saw Iori Yagami, who told him that only those "of the bloodline" could control Orochi's power.

Rugal's non-canon appearance includes King of Fighters '98 and King of Fighters 2002, which he appeared as a final boss on both. Rugal also appeared in Capcom VS SNK 1 and 2, with CVS 2 having him take an alternate form of himself called God Rugal (or Ultimate Rugal) in which he asorbed the energy of Akuma. Toshimitsu Arai voiced Rugal since his debut, but Norio Wakamoto voiced Rugal in KOF 2002.