The Chainsaw Man movie mixes hand-drawn animation with CGI — just like Demon Slayer: Infinity Castle

Mappa’s upcoming Chainsaw Man – The Movie: Reze Arc masterfully blends 2D and 3D art, echoing Ufotable’s Demon Slayer: Infinity Castle by pairing 3D environments with 2D character models. At New York Comic Con, Mappa made its first appearance with a panel featuring assistant director Masato Nakazono, supervising producer Manabu Otsuka, and CGI producer Yusuke Tannawa, offering fans a behind-the-scenes look at the film.

During the panel, the team addressed questions about the techniques used to merge 2D and 3D animation, showing early blueprints and prototype footage while subtitles were read aloud for attendees.

“In the Reze Arc, the role of CGI is to complement each production process in a balanced way, in order to maximize the artistic expression of the hand-drawn animation,” CGI producer Yusuke Tannawa said (via translator). “We create 3D background models for key scenes to ensure accurate placement and scale that aligns with the director’s intent. In scenes that take place inside the cafe and in the nighttime classroom, the 3D CG layout helps maintain precise positioning between characters. While [during] the city battle sequences, it enables dynamic camera movements that would be difficult to achieve otherwise.”

Infinity Castle employs similar techniques, merging 2D characters with constantly shifting 3D corridors of its titular location. At times, the line between 2D and 3D blurs — like during Shinobu’s showdown with Upper Rank demon Doma. Cinematic CG enhances transitions, emphasizing scale, reflections, and dynamic action. The same could be said about the upcoming Chainsaw Man movie.

“In particular, for the battle scenes, we reproduce the texture of hand-painted backgrounds in CG, allowing for dynamic visual composition within the aesthetic of traditional animation,” Tannawa said

The Chainsaw Man panelists also explained how using 3D CG models helps maintain positions and gives background objects surrounding the characters a realistic look. However, unlike Infinity Castle, instances of 3D models on screen are few and far between in Reze Arc.

“Although all the characters in this film were drawn by hand, 3D CG guide models were extensively used during the layout stage to simulate the best possible compositions before moving into the drawing phase,” Tannawa said. “In addition to the Denji Chainsaw Man models from the TV series, new models were created for Reze/Bomb and Beam and shared with the animation staff to support the overall production workflow. Many of the vehicles are also represented in 3D CG, contributing to the film’s sense of realism.”

Footage shown at the panel revealed 3D layouts of classrooms and cityscapes, including a sweeping shot over a damaged section of the streets. We also saw T-posing models of the Bombs and Denji as Chainsaw Man, displayed alongside fully 3D-rendered vehicles of every type.

We’ve said it before, but the days of CG having a terrible reputation within anime are disappearing in real time. CG is carving out its own artistic space, revealing a unique kind of beauty that blends with traditional 2D. Films like Infinity Castle and Reze Arc show how full 3D animation can deliver breathtaking, action-packed battles that rival the best of traditionally produced anime. At its peak, the technology doesn’t just support the art; it becomes indistinguishable from it.