Golden Kamuy: Inazuma Goutou to Mamushi no Ogin/Shimaenaga

Released in 2025 as part of the Golden Kamuy franchise, this OVA is a direct continuation of the series' tradition of adapting popular side stories from Satoru Noda’s original manga. Produced by Brain's Base, the episode focuses on two of the series' most colorful supporting characters, the serial killer Inazuma Goutou and the elusive Mamushi no Ogin, alongside the fan-favorite Shimaenaga birds. The project was designed to expand upon the darker, character-driven vignettes that characterize the franchise's unique blend of historical drama and absurdist humor.

The animation direction for this installment seeks to maintain the gritty, high-stakes atmosphere established in earlier seasons while leaning into the peculiar, often comedic charm of the series' minor antagonists. By adapting these specific character arcs, the studio aimed to provide deeper context for the motivations and chaotic interactions that populate the hunt for the gold. Upon its release, it was received as a faithful expansion of the source material, appreciated by fans for its focus on the eccentric individuals that populate the harsh landscape of Hokkaido.