(translated roughly as "Grandchild – First Half 3D" ) is a legendary piece of vaporware within the deep niche of late-1990s Japanese indie game development. Purported to be a fully 3D, psychological horror adventure game for Windows 95/98, it is believed to be a technical and narrative sequel or companion piece to the earlier, equally obscure 2D title Mago . No verified playable build, ISO, or even a complete screenshot set has ever surfaced publicly. The project is primarily known today through a single, low-resolution promotional render, fragmented developer blog posts from the Web 1.0 era (archived on GeoCities and Infoseek), and passing mentions in early Japanese BBS horror discussions.

"Mago" is a popular used for restyling and transforming footage into 3D animations or other stylized looks.

The engine reportedly featured: