Yoichi Miyaji is the producer leading Kadath, the production company he founded in January 2026, and its first project, the dark fantasy JRPG Under Mythos, planned for 2028 on PC and Switch.
Yoichi Miyaji founded the production company Kadath Co., Ltd. in January 2026 and is its producer. Kadath announced its first project, the dark fantasy JRPG Under Mythos, on September 10. The game is planned for release in 2028 on PC via Steam and Nintendo Switch. In that first announcement, Kadath stated a goal of restoring Japan-originated JRPGs and original IP, and Miyaji framed the project as an indie-minded effort to court fans from the planning stage.
The second report places Miyaji at the head of a small, creator-first production house that pulls staff from several studios as needed. Atsuko Nishida designs the characters. Matrix, Liz, and Taiwan's iSWEETY are among the developers helping. Under Mythos is the test case for whether that staffing model can deliver an original JRPG.
The game itself casts the player as a cat searching for its Mother. The cat arrives at a mysterious hot spring inn where otherworld residents soak and works there entertaining guests. The system combines inn management simulation with extraction: players explore dungeons for ingredients and resources, fight action battles against grotesque transformed beings, and return safely to put the ingredients and rewards back into running the inn. Developing the inn produces new encounters that lead back to exploration, and the familiar world gradually mutates into an unpredictable madness as the story progresses.
Written with AI from the cited Yomimono stories below, each itself sourced. See our editorial policy. Every fact links the story it came from.
Structured graph also available as JSON at /public/entities/yoichi-miyaji.
CC BY 4.0.
KADATH, a production company founded in January 2026, is working on Under Mythos, a dark fantasy JRPG planned for 2028 on PC and Switch. Yoichi Miyaji leads it; Atsuko Nishida designs characters. The player is a cat searching for Mother who ends up working at a Japanese hot spring inn, with a Cthulhu mythos world beneath the calm. Matrix, Liz, and Taiwan's iSWEETY are among the developers helping.
Kadath Co., Ltd. announced on September 10 the dark fantasy JRPG Under Mythos, planned for release in 2028 on PC via Steam and Nintendo Switch. The studio was founded in January 2026 by producer Yoichi Miyaji, whose credits include the LUNAR and GRANDIA series, and Under Mythos is its first project. The protagonist is a single cat that wanders into another world while searching for its Mother, arrives at a mysterious hot spring inn where otherworld residents soak, and works there entertaining guests while wishing to reunite with Mother. The game system combines hot spring inn management simulation with extraction: players explore dungeons for ingredients and resources, fight action battles against grotesque transformed beings, and return safely to put the ingredients and rewards back into running the inn. Developing the inn produces new encounters and experiences that lead back to exploration. The familiar world gradually mutates into an unpredictable madness as the story progresses.