Sokusan (急速な計算; Rapid Calculation) is one of the meditative samurai techniques of the Naibudō discipline. Sokusan manipulates the chakra located within the brain of the user, accelerating the electricity and chemical activity channeling through it. Sokusan allows the user to drastically expedite their mental production, allowing them to think, problem solve, deduce solutions, and dwell on and process information, and consider multiple outcomes of their decisions simultaneously, calculating them at superhumanly hastened speeds. The speed and degree of efficiency depends on the chakra control, experience, and intelligence of the samurai. Samurai tacticians and war generals often specialized in Sokusan down to a finessed art.