3D Monster Maze is a computer game developed from an idea by J.K.Greye and programmed by Malcolm Evans in 1981 for the Sinclair ZX81 platform with the 16 KB memory expansion. The game was initially released by J. K. Greye Software in early 1982 and re-released later the same year by Evans' own startup, New Generation Software. Rendered using low-resolution character block "graphics", it was one of the first 3D games for a home computer, and the first game incorporating typical elements of the genre that would later be termed survival horror.
3D Monster Maze puts the player in a maze with one exit and a hostile monster, the Tyrannosaurus rex. There, the player must traverse the maze, from the first-person perspective, and escape through the exit without being eaten.
J.K.Greye Software went on to become a very successful games company publishing 6 Games Tapes for the Sinclair ZX81 - 2 in 3D - 3D Monster Maze & 3D Defender, both designed by J.K.Greye and programmed by Malcolm Evans.
New Generation Software went on to become a well-known software firm with the Sinclair platform and continued to pioneer the 3D gaming technology for ZX81 and the later model Sinclair ZX Spectrum. The press immediately gave the game a title of a "firm favourite" of the ZX81 users. Decades later, it became popular with the retrogaming community, inspiring remakes and fuelling ZX81 emulation projects.
Source: Wikipedia, "[en.wikipedia.org/wiki/3D_Monster_Maze 3D Monster Maze]", available under the CC-BY-SA License.