Berserk

Berzerk is a multidirectional shooter designed by Alan McNeil and released for arcades in 1980 by Stern Electronics of Chicago. Following Taito’s Stratovox, it is one of the first arcade video games with speech synthesis. Berzerk places the player in a series of top-down, maze-like rooms containing armed robots.

When the game begins, the player controls a green stick man on the left of the screen. In two-player games, the second player controls a purple stick man on the right of the screen. Each player plays until they lose a life, allowing the other player to have a turn.
Using a joystick and a firing button that activates a laser-style weapon, the player navigates a simple maze filled with many robots, who fire lasers back at the player character. A player can be killed by being shot, by running into a robot or an exploding robot, getting electrocuted by the electrified walls of the maze itself, or by being touched by the player’s nemesis, Evil Otto.

As a player’s score increases, the colors of the enemy robots change, and the robots can have more bullets on the screen at the same time.[3] Once they reach the limit of simultaneous on-screen bullets, they cannot fire again until one or more of their bullets detonates; the limit applies to the robots as a group, not as individuals.