Succeeded by: Spike Chunsoft
Chunsoft, while little-known in the west, is the originator of the "Novel" format of games, with Otogirisou (1992) being the first videogame ever to use the now-common format of full screen text on a background image plus occasional selection branches. Chunsoft introduced the series with the "Sound Novel" brandname, which they trademarked. The "Sound Novel" name is just as popular as "Visual Novel" in Japan.
While "Novel" games are mostly associated with anime art in the west, Chunsoft's original Sound Novels did not use the art style for most part. Instead, they use various art styles, sometimes even using styles very rare in videogames. The first game, Otogirisou, used 2D pixel art (due to limitations of the ROM size), but later games like Kamaitachi no Yoru used photographs or 3DCG scenery combined with silhouettes, and few games such as Machi or 428 even went as far as to using a large number of filmed-on-location live stills using real actors.
Chunsoft games also feature experimentation in the structures of the narrative. Kamaitachi no Yoru had a standard branching plot; Otogirisou and Imabikisou had the narrative moving back and forth across a mesh of multiple subplots; and Machi and 428 had what they called a "Multi Fragment" narrative structure, which had multiple protagonists running in parallel, interlocked with each other.