See instructions in the game
Zero Tolerance is a 1994 video game developed by Technopop and published by Accolade exclusively for the Sega Mega Drive/Genesis video game console. It was one of the few Mega Drive/Genesis first person shooters, besides Bloodshot and the Duke Nukem 3D port.
Zero Tolerance is made up of 40 levels spanning three separate areas: the space warship Europe-1, an abandoned merchant freighter, the heavily fortified central command building for the Planet Defense Corps, and the sub-basement areas of that building. The object of the game is to kill all of the enemies on a level and then proceed to the exit, which is either a staircase or elevator leading down to the next level.
However, nothing prevents the player from heading straight towards the exit without killing all of the enemies. If this is done, the player is simply not given any passwords until the entire area is finished.
Once a character is killed that character will be listed as "deceased", and becomes unavailable for playing. The player can choose from a total of five different characters; once they are all deceased the game is over
The game supported connecting two Genesis/Mega Drives via a special link cable using the second joypad ports for a multiplayer mode. The cable was originally supposed to be shipped as a pack-in with the game. However this was changed in a last-minute decision and a coupon for ordering a free cable was added instead
Zero Tolerance features five different characters from which the player can choose to play, each one being a member of a crack commando squadron of the Planetary Defense Corps, an elite group codenamed Zero Tolerance. Each individual character has a unique ability which has a slight effect on gameplay, as well as different items they start with at the beginning of the game. All characters are named after the game's developers.
GamePro gave the game a mostly positive review, commenting that "First-person games like Zero Tolerance really put pressure on a system's processor, but Accolade has done a good job here: The anxiety caused by an adversary careening around a corner or the twitching body of a gunned-down spider is severe." They additionally praised the large and labyrinthine levels, cooperative multiplayer ability, and limited but effective sound effects, though they criticized a few elements such as how slowly the player character turns.