Xybots

Xybots was produced by Atari Games in 1987.

Run your human through mazes with a 3-D over-the-shoulder view. Shoot tons of nasty robots that are out to get you. Exit each level to progress to a new maze, with boss levels and the option to buy upgrades between levels.

This is possibly one of the first 3-D shooters ever made. While there are none of the full, free motion effects of the traditional modern day 3-D engines, you are able to change perspectives on the fly.
The names of the characters are Captian Ace Gunn and Major Rock Hardy.

This game is like playing a primitive version of Doom, or a futuristic, first-person 3-D Gauntlet game.

The game also got ported to many computers back in the day including the MSX, ZX Spectrum, C64, Amiga, and Atari ST just to name a few. Also got a port to Atari’s own Lynx handheld in 1991.