3D Monster Maze is a survival horror computer game developed from an idea by J.K. Greye and programmed by Malcolm Evans and released in 1981 for the Sinclair ZX81 platform with the 16 KB memory expansion. The game was initially released by J. K. Greye Software in December 1981 and re-released in 1982 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 one of the first games 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 six Game Tapes for the Sinclair ZX81; two use 3D graphics: 3D Monster Maze and 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 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. Gameplay The game uses an 18-by-16 cell maze which is randomly generated. Initially the T. rex lies in wait. Once the player starts moving, the beast begins hunting. Thereafter, the T. rex may either calm down (if the player goes into a part of the maze that is far enough away), or become more active as the player comes closer. If the T. rex gets a direct view of its prey, the monster will run directly at the player. The T. rex anxiety level, reported to the player as a statement in the status line, provides an indirect clue to the player's relative distance from the monster. These statements are: REX LIES IN WAIT, followed by HE IS HUNTING FOR YOU, FOOTSTEPS APPROACHING, REX HAS SEEN YOU, and RUN HE IS BESIDE YOU or RUN HE IS BEHIND YOU. The player's speed is greater than the monster's, thus it is possible to escape by running (unless the player is trapped in a dead end).