Nira Oni is a captivating fangame set in the eerie universe of Ao Oni, designed for Windows. Players will join a group of characters—Hiroshi, Takeshi, Mika, Takuro, and newcomers Cassey and Ryan—as they navigate the unsettling environment of an abandoned hospital. The game combines elements of exploration and survival within a puzzle framework, challenging players to solve mysteries and avoid terrifying creatures known as oni.

As the story unfolds, Hiroshi becomes separated from his friends, and players must guide him through a series of chilling encounters while searching for a way to reunite and escape. The game emphasizes atmosphere and tension, creating an immersive experience that keeps players engaged. With its intriguing narrative and challenging gameplay, Nira Oni is a notable addition to the puzzle genre.