Sakugan

Far in the future, the human beings were pushed into the deep underground world called Labyrinth and they are living shoulder-to-shoulder. The Labyrinth has several colonies with severe settings such as one having an insanely high temperature, while another is full of gold and silver. Among those, in a colony of Pinyin, resides a curious nine-year-old girl named Memempuu and her father Gaganbar. As workers aiming for survival, they live with the lowest profession of riding a working robot to dig ore.