Taizo Hori, a seasoned digger, descends into the depths beneath the surface to confront the creatures that lurk in the darkness below. Armed with the ability to carve tunnels through rock and soil, he navigates an underground labyrinth populated by hostile beings that threaten the world above. His mission demands both strategy and courage as he works to clear out these subterranean threats level by level, using his unique skills to outmaneuver the dangers that await in each chamber.