Pewku

Pewku is an Ussal crab (see below) that has been a favorite pet of several Matoran. On Metru Nui, she pulled carts for her owner, Orkahm, and after the Great Cataclysm Whenua took a liking to her and suggested they bring her to Mata Nui. Sometime over the next thousand years, she passed into the care of Onepu, who rode her in the Great Ussal Races. Eventually, she was retired from racing, instead giving "taxi crab" rides between Po-Koro and Onu-Koro. It was on this job that Takua met her, and he later on adopted her; She would later be Takua's and Jaller's steed and traveling companion in their search for the Toa of Light. When Takua became Takanuva, he gave Pewku to Jaller, but now that Jaller has become a Toa Inika, it is unknown who will take custody of Pewku.

Pewku's name used to be spelled "Puku", and was changed by Takua shortly after the Bohrok invasion. A little while later, just before the search for the Toa of Light, Pewku evolved to her current form, larger than most Ussal crabs.

Owner
When Takua became a Toa, fans speculated her fate. Some say she went to Jaller. But Jaller became a Toa Inika, so it is assumed that she went back to Onepu.