Kralhi

The Krahli are the prototype of the Vahki law enforcers in the BIONICLE legend. Designed by the Matoran engineer Nuparu and a team of Po-Matoran builders, the Krahli were concieved as the protectors of the peace in Metru Nui. They stopped lawbreakers by firing energy bubbles at them, which drained the Matoran of energy and fed it back into the Krahli. Unfortunately, this made the Matoran too weak to carry on working, and the Krahli were put out of service. They refused to be shut down, and the Matoran, with the help of the new Vahki, was able to drive most of them out of the city. Some still linger in Ko-Metru and the Archives, but they refuse to be moved. On their mission to save the Matoran from the Makuta, the Toa Metru found the banished Krahli, who were working for a Matoran named Mavrah. In a huge battle between the Toa Metru, Mavrah, the Vahki, the Krahli and a group of sea Rahi, the Krahli were destroyed forever.