OverBlood is a survival horror game that follows Raz Karcy as he tries to uncover the truth behind the scientists' plans and find a cure for the terrible disease that has infected him. A team of scientists at the Lystra Laboratories research center have been conducting genetic experiments, but their system malfunction leads to Raz's release from a cryogenic container.
The gameplay of OverBlood focuses on exploration, puzzle-solving, and combat in 3D environments. The player controls Raz for most of the game, with occasional opportunities to play as other characters, such as Pipo, a small robot that can perform special tasks. Some sequences involve rapid button-pressing similar to arcade-style "interactive movie" games.