Microcosm is a 3D action shooter that takes place entirely within the human body. The story follows a player who must enter the body of Anton Korsby, the president of CyberTech Industries, to destroy a virus that threatens to take over his body and ultimately destroy himself and CyberTech.
The player's mission is to navigate through various parts of the anatomy, blasting viruses and enemy ships while collecting power-ups and upgrading their craft. The ultimate goal is to reach the brain and stop Grey M, the entity controlling Korsby's body.