Back in the year 2000, Slitherine Software announced the release of what was to be the first first-person shooter for a handheld. Tyrannosaurus Tex followed the story of a maverick cowboy through 28 levels with six different types of guns and ten different types of enemies. While the game was actually 2D, because of the first-person perspective, it would have played and looked a bit like a 3D game.
The game was to come out in late 2000 and then late 2001. Originally, Eidos was to publish the game, but they dropped out and when TT missed showing up at E3 the rumors were that the game was dead before arrival. However, IGN was able to take a look at the game and stated that it had fast paced action and a smooth animation to it.
The game itself was to start off with a training level where you were taught how to play the game and blue text would appear on screen to give you hints and tips on what to do. Since we are talking the early Gameboy color here it is no surprise the world of Tyrannosaurus Tex was mainly halls and corridors kind of like the first Wolfenstein. All the object in the game are drawn spites and the enemies were drawn at different sizes to emulate the close and far effect.
The enemies themselves also looked a bit plain with not much detail. Most enemies only had a few colors at most and when you killed them, they exploded into tiles. From what we can gather, the idea was to have violence without making it to gory or maybe it was just the system limitations. You could pick up different weapons and hit the select button to choose one and by hitting start, you could view the world map.
In the end, the game was never released and sources claim Slitherine wanted to release a ROM of the game, but the rights went back to Eidos. Personally, I would not have played this game, but the reviews did claim it was a pretty good game considering. Unfortunately, we will never know.
UPDATE 2016: The rights to the game were acquired by Piko Interactive and the game was finally released. To find out more visit here: https://pikointeractive.com/blog/its-official-tyrannosaur-tex-gbc-is-ours/