The rules of Earth Rumble are simple: knock the other fighter out of the ring with earthbending and you advance to the next round. The fighter who defeats all others has to challenge and defeat the winner of the past Earth Rumble competition for the title of Earthbending Champion and the prestigious Earth Rumble belt. To make things more interesting, Xin Fu would sometimes offer prize money to an audience member that believed they could defeat the Earthbending Champion.