To understand the search, you must understand the weight of Mugen Train (Infinity Train). Released as a film (and later as a TV arc), it shattered box office records in Japan, surpassing Spirited Away .

The Mugen Train arc changed the landscape of Demon Slayer forever. It gave us one of the most heartbreaking, visually stunning, and emotionally charged moments in anime history: the death of Kyojuro Rengoku.

The death of Kyojuro Rengoku is widely regarded as one of the most emotionally powerful moments in modern anime. In the editing community, this scene has become a gold standard for "Twixtor" showcases—a process that uses sophisticated motion estimation to generate new frames, allowing for ultra-smooth slow motion that highlights the intricate details of Ufotable's animation.