Haohmaru (覇王丸) and Kibagami Genjuro once trained under master Nicotine Caffeine. They were very close friends. One day, master Nicotine told them they would battle to determine who would learn the secrets in a magical scroll to increase their fighting ability. Genjuro won, but almost killed Haohmaru; in response, Nicotine expelled Genjuro. After this, Haohmaru traveled the lands perfecting his sword skills, and searching for worthy challengers. Hearing of Amakusa's return into the world, Haohmaru sets out to defeat him. He does so with the assistance of Nakoruru, Hanzo, Galford, Charlotte and Ukyo. On his many travels, Haohmaru found a village that had been slaughtered to the last man, save a small child. He took in the child, Shizumaru, and trained him in the fighting arts.
In Samurai Shodown 5, Haohmaru has just defeated an opponent and let him go when Yoshitora arrives, calling Haohmaru a fool for letting an enemy go. Upon seeing Yoshitora's swords, Haohmaru challenges Yoshitora to a duel but Yoshitora declines the offer, stating he doesn't have time, but vows they will fight the next time they cross paths. Haohmaru then reveals that he is going to Hinowa because the strongest warriors are meeting there and whether Yoshitora would join him in the journey, but again Yoshitora declines. Haohmaru then tells Yoshitora to go there if he changes his mind and runs off. Upon reaching Hinowa, Haohmaru finally meets Gaoh, who says that he will build a new country. Gaoh then tells Haohmaru that he has to kill him. After beating Gaoh, Yoshitora shows up for the duel and formally introduces himself. Before the fight begins, Yoshitora asks Haohmaru to join him and help him build a new country. Haohmaru then says that if he loses, he'll join him. After the battle, Haohmaru reflects on his samurai life.
In Warriors Rage, Haohmaru is now an older, yet still skilled and active swordsman at the age of 47. After hearing that his adopted niece Mikoto had departed from the temple where she was raised, Haomaru follows her to the cursed island of Riten Kyo. There, he grows aware of the evil entity at work there, and departs on a journey to stop the Razor Trio, and as well as duel worthy opponents along the way. In the end, Haohmaru eventually reaches Mikoto at the Riten Kyo. Shortly after killing Oboro, he retrieves Mikoto and reveals some of her past.
|Secret Cyclone Slash||+|
|Crescent Moon Slash||+|
|Renting Tremor Slash||(while dashing), +|
|Sword Slash Attack||+|
|Rice Wine Whack||+|
|(Rage) Secret Move||+|