The Lava Rat was a small rodent Rahi that inhabited the Island of Mata Nui after the Great Cataclysm, specifically the volcanic Ta-Wahi region. It was immune to being burnt by fire and was known for its ability to spontaneously burst into flames. An old Matoran legend tells the tale of a Lava Rat trying to get across a body of water on the back of a Takea Shark - both were uneasy, because the Lava Rat was afraid the Takea would eat it and the Takea was afraid the Lava Rat would burst into flames.