Alien Arena [Game has no sound]

Alien Arena is a rarity: Duncan Brown programmed it in assembly language for Williams hardware, working on his own for a year and installing it on a recycled Stargate cabinet in the arcade he himself ran. It pits two players, Thor and Zespar, against each other in an enclosed arena with a capture-the-flag dynamic, in matches timed by coin.

It's an uncommon example of almost artisanal development during the golden age of American arcades, outside the circuit of the big distributors. It's preserved today more as a historical curiosity than as a played classic, documented mainly thanks to its author's own account.