Koei Tecmo’s research and development (R&D) expenses in the recently ended fiscal year (April 1, 2025 – March 31, 2025) were 39% higher than the previous year. As reported by GameBiz, a big part of these expenses went toward further development of Koei Tecmo’s proprietary game engine, the Katana Engine.
Katana Engine is Koei Tecmo’s primary game engine, currently used for the majority of their titles. It’s compatible with a variety of genres – from 3D action games like Dynasty Warriors: Origins and Rise of the Ronin, to tactical sims like Nobunaga’s Ambition. Throughout the years, the engine has been tuned for both photorealistic lighting rendering and the “non-realistic,” anime style you see in Atelier games. It supports procedural content generation, which allows developers to generate terrain models based on sketches and create facial expressions for characters based on 2D assets (source: Denfaminicogamer).
According to Koei Tecmo engineer and R&D lead Hirosato Mishima, the company is committed to developing its own engine as opposed to using third-party engines, as this significantly shortens the iteration process (trial-and-error) of turning ideas and theories into reality.
“Koei Tecmo has the technical capabilities to build top-tier game engines completely in-house. We’re one of the rare studios able to prepare our own development environment for new [gaming] platforms as they appear. We don’t have to wait for middleware providers to issue updates; we can immediately act on new or interesting ideas.” Mishima believes that this kind of self-sufficiency is “an indispensable qualification” for any game developer aspiring to compete in the global market.
