: Goku trains under Roshi's mentor, Master Mutaito . The most iconic moment occurs when Mutaito demonstrates how to split a waterfall in two using only his ki —a feat Goku struggles to replicate but eventually manages in a moment of protective anger.
The central feature of this episode is to refine his mental discipline and ki control. After failing to defeat Mr. Popo in the present, Goku is sent back roughly 300 years into the past via the "Room of Time". Dragon Ball (Dub) Episode 129
: This episode marks a shift from purely physical training to the spiritual and mental focus required for high-level combat. : Goku trains under Roshi's mentor, Master Mutaito