Bionicle Trilogy/Settings

Mata Nui
The main home of the Matoran and the sole setting of The Tales of the Toa, Mata Nui, named after the Great Spirit, is a large tropical island located on the surface of the planet of the Endless Ocean. When Mata Nui fell into a coma due to Makuta, the island was created as a last-resort place for the Matoran to be safe from the evils of Makuta. Following the Great Cataclysm, the Toa Metru landed on the shore of the island, which they named in honour of the Great Spirit. They scouted out the land to find areas where they could build villages for the Matoran of Metru Nui to live, and named several landmarks. When the Matoran were awakened on Mata Nui followed the Great Rescue, they constructed the six Koros from the pieces of the Airships in the designated spots on Mata Nui, under the direction of the Toa Metru, who had become Turaga.

For one thousand years afterwards, the island was plagued by attacks from Rahi controlled by Makuta and his Infected Kanohi. Once the Toa Mata arrived, they put an end to the attacks by confronting and defeating Makuta, only for him manage to release the Bohrok, with the island being ravaged by their attempts to level it of everything. However, after the defeat of the Bahrag, the Bohrok were reprogrammed and made to begin rebuilding the island. When Takua found the Avohkii, the island was once again badly damaged by the Rahkshi while they were searching for it. After Takanuva defeated Teridax and rediscovered Metru Nui, the Matoran constructed a system to allow them to work on repairs to both Mata Nui and Metru Nui while continuing to live on Mata Nui.

Metru Nui
The original home of the Matoran and the main setting of City of Legends, Metru Nui is a massive metropolitan city located within a dome. Receiving light from two mysterious "suns" and possessing a grey sky with stars that are said to be reflections of Mata Nui's thoughts.

The Coliseum
Located at the centre of Metru Nui, the Coliseum is a massive building that towers over all of the six districts of the city. Stated to be the first building of Metru Nui built, it was Turaga Dume's residence and where he controlled the technology of the city, as well as a power plant that supplied most of the power to Metru Nui and a storage facility for items critical to the city. The arena around it, mainly used as the site of the tri-monthly Alkini tournaments, contains enough seating for every single Matoran in Metru Nui, and was used by Dume to make major announcements, overlooking the arena in a specially made box that could be raised or lowered by his will. The arena floor was made up of hundreds of Protodermis columns which could be raised or lowered at will, producing "waves" for the players to ride. A complex system of retractable Chutes was also stationed in the arena, and would be extended or retracted randomly for the players to go through. When not involved in Alkini tournaments, the Vahki would also train here.

During Makuta's impersonation of Turaga Dume, he installed a sundial in the throne room and began storing Matoran Spheres in the basement, first testing the devices on Jaller, the only Matoran who learnt the truth about the false Turaga. Later, the Toa Metru attempted to present themselves to the city, only for Makuta to use the arena's manipulative fields to humiliate them before capturing Onewa, Whenua and Nuju, although Vakama, Nokama and Matau were able to escape. During Makuta's successful incapacitation of Mata Nui, he had the Vahki order all Matoran to the Coliseum and force them into the Matoran Spheres. The Toa Metru managed to save seven spheres containing Jaller, Hahli, Kongu, Hewkii, Ahkmou, Kopeke and Nuparu, although Ahkmou's sphere was lost after their transport was attacked by Makuta and the Po-Matoran was ultimately saved by Makuta himself. Makuta then drained the energy from the Coliseum's power plant to restore his energy, in the process emitting a energy pulse feedback that destroyed much of Metru Nui.

Later, during the Visorak occupation of Metru Nui, the Coliseum was used as the main base of operation for the horde, as well as Roodaka and Sidorak's residence. It was modified for defence, with new gates and Rhotuka launchers mounted into the walls. The Coliseum also became covered in webbing that connected to every other district of the city, the webs being so thick that Sidorak and Roodaka were able to walk across it and use the Destral Cycle to quickly transport themselves across the city. The Toa Metru were mutated into the Toa Hordika here, and later, Vakama, giving into his Hordika side, brought five of the captured Rahaga here to present to Sidorak. During the final battle for Metru Nui, the Toa Hordika, after redeeming Vakama, were able to defeat the Visorak horde with the aid of the Rahagah, Keetongu and the true Turaga Dume. After the departure of the Toa Metru to Mata Nui, Dume, Keetongu and the Rahagah lived in the Coliseum for a millennium, slowly repairing Metru Nui. Following Makuta's defeat by Takanuva, the Matoran rediscovered Metru Nui and began working to repair the Coliseum, although they continued to live on the island of Mata Nui.