The Serum

, additionally known as the Performance enhancing formula is a biogenic chemical compound made to augment the human body. After Takumi Uchiha had his partner, Naien, arrested for embezzlement he found in his notes a formula which could apparently augment a person’s body to superhuman levels. He began research on the formula, hoping to eventually sell it. Unknown to him, Naien had tampered with it to spite him. Consequentially the completed formula was unstable and exploded in Ryūken Senju's face. He spent the next week in the hospital recovering. After finally regaining consciousness he found his mental and physical functions have been greatly enhanced. It was later learned that exposure also causes severe insanity which was the primary motivation for him. He gained superhuman strength and durability as well as improved dexterity. Earlier tests suggested that the process increased strength over 1000% but it was even more efficacious for Ryūken, who could punch Takumi hard enough to knock him back over two dozen feet with enough momentum to fell a metal lightpost that crossed his path and allowed him to suspend the weight of a cable car full of passengers with one hand. His improved reflexes and agility allowed him to easily defeat numerous police officers in hand-to-hand in a few seconds and to match the swiftness and acrobatic prowess of Takumi.