|“||There is nothing quite so... amusing... as Matoran at war with each other. There they are, with their powerless masks and their little weapons, trying to look formidable as they march into battle. One has to laugh.||”|
–Narration, The Mutran Chronicles
Minor disputes between the Po-Matoran and the Ta-Matoran evolved into a full scale war after the Po-Matoran sank some transport barges and the Ta-Matoran melted a Po-Metru warehouse using molten protodermis. The Onu-Matoran then allied with the Ta-Matoran while the Le-Matoran allied with the Po-Matoran. The Ko-Matoran attempted to intervene, but, due to being ignored, later joined the Po-Matoran. The Ga-Matoran attempted to stay neutral, but failed and allied with the Ta-Matoran.
Arguments between Matoran escalated into combat, and the denizens of Metru Nui began fighting in the streets. Work was eventually abandoned by most Matoran, and large sections of the city were destroyed during the war. The Turaga at the time was ineffective, and could not prevent the fighting.
Miserix eventually ordered his trusted lieutenant, Teridax, to halt the fighting. Teridax took a large number of the Matoran fighters and locked them in the Archives. He then released the various exhibits on the Matoran, killing a large number of them. The battle would later be known as the Archives Massacre, and put an end to the fighting. However, it gave the Makuta a very bad reputation in Metru Nui.
Because of the lack of work in Metru Nui, the Great Spirit Robot wasn't properly maintained, which caused Mata Nui to slowly die. A Toa Team led by Jovan journeyed to the Southern Continent to retrieve the Ignika. From there, they went to Karda Nui, where one of the team's members was sacrificed by wearing the Kanohi Ignika to save Mata Nui.
In order to prevent similar problems, the Makuta were each assigned various regions of the Matoran universe to watch over. Teridax was assigned Metru Nui, as a prize for stopping the war. The Matoran of Metru Nui came to view the Makuta with distrust and fearful respect.