One day Ryu Kumon's father had an encounter with Genma Saotome. After Genma found out about the Kumons' financial problems, he gave Ryu's father a scroll containing the deadly secret art of Yamasenken, a.k.a. Fist of One Thousand Mountains. This led the elder Kumon to believe that he could use the Yamasenken to restore his dojo, but when he used the technique he ended up destroying it, causing his own death when it collapsed on him. With his last moments of life he gave Ryu the scroll and told him to find the one containing the companion Umisenken.
Before his death he had mastered three moves of the Yamasenken style:
- Dokuja Tanketsu Shou ("Poisonous Serpent Searching Hole Palm"): A fierce open palm snake strike to the chest area.
- Kaichü Houju Satsu ("Jewel Held in One's Pocket Kill"): an armlocked bear hug submission maneuver while holding one arm behind the back.
- Mouko Kaimon Ha ("Fierce Tiger Opening Gate Defeat"): A powerful kick through the opponent's guard by separating their arms.