In the first-person shooter Zombeer the protagonist simply called "K" is a student. He wakes up hungover in a bar when he receives a message on his cell phone from his girlfriend Karen. Apparently K drunk too much at a Halloween party and made moves on a cheerleader in zombie costume. To take revenge Karen says will go with college a party with the principal Colon Duty instead. K has to prevent this, but there are bigger worries as well as a virus has turned all people into zombies. K has to fight them, but he is bitten too. He needs to prevent the virus from spreading by chugging zombeer as a temporary antidote to manage a meter that is always present near the bottom of the screen. If he does not find enough beer in time he turns into a zombie and the game is over. If he drinks too much he wobbles making the harder to aim and his sight is severely distorted. The game has cartoon-like graphics and a humorous tone that references classic zombie movies.
K starts with a pink dildo and and a nailgun as basic weapons, and later on more powerful ones can be found such as an octogun, grenades, and a sniper rifle for a single section. K travels among the urban ruins to the school where the principal zombie spends time biting girls and driving the zombies to conquer the city. There are also some short quick time events. Next to regular movement K can run, shoot, aim with iron sights, crouch, jump, interact with the environment and use a flashlight. When he is hurt a red border appears around the screen and he can also die, but health regenerates automatically after a while and there is no separate health meter. Next to guns and ammo there are many optional collectibles. The game has many vending machines where an unlimited amount of zombeer can be accessed, but a mini-game based on timing a spinning wheel needs to be completed first. If the sequence is not performed correctly, additional enemies appear.