The surface world is contaminated by toxic fungi, and what remains of civilization is buried in the refuse of the old world. A discarded maintenance robot finds a girl named Toriko near death in a scrapyard and nurses her back to health. The robot and a decommissioned AI called factoryAI realize the implications: Toriko may be the last surviving human, fragile and unable to survive exposure to the outside. They build her a terrarium as a refuge and the robot ventures into the wasteland to gather what she needs to live—fighting the vagrant machines and mutated creatures that have claimed the ruins. Void Terrarium is a roguelike dungeon-crawler in which the terrarium's condition and Toriko's health are the primary stakes of every run.