The Bionicle story is set in a science fantasy world and is primarily told through the book series Bionicle Chronicles, Bionicle Adventures, and Bionicle Legends, as well as through comic books published by DC Comics. Four films have also been made.
Spherus Magna is a fictional planet and home of the Great Beings (the creators of the Matoran Universe). It housed seven tribes of warriors governed by the 'Elemental Lords' capable of controlling the substances that the different tribes represented (namely Fire, Water, Jungle, Ice, Sand, and Rock). Eventually, a substance later dubbed 'Energized Protodermis' was found in the Ice region and the dispute over extraction rights led to a war with the Element Lords as generals and the warriors as soldiers. Upon victory, the Fire Tribe began to extract the substance; but this split the planet in pieces, and the Great Beings created a massive robot, known as Mata Nui, to study other worlds and later to reform Spherus Magna. Thereafter the planet broke into three new worlds: a desert world (Bara Magna), a jungle moon (Bota Magna), and an ocean moon (Aqua Magna), whereupon the Agori and warriors renamed the planet Bara Manga and established a legal system to prevent another war, based on trial by combat wherein each region was represented by a champion, called the 'Glatorian'. When his longtime rival Makuta Teridax was destroyed, Mata Nui rebuilt Spherus Magna and changed the desert of Bara Magna into a massive, garden-like region, where the Agori, Glatorian, and other members of the Matoran Universe and Spherus Magna could live in peace.
The largest arena, located in the city of Atero, is one of the few remnants of the old civilization, where the annual contest to find the best Glatorian was held. It is positioned to the north of Vulcanus, on an island in the great waterfall of Skrall River. In the last contest, the arena is destroyed by a massive Skrall invasion force, killing many Glatorian and Agori. This was the beginning of open hostility between the Rock Tribe and those who lived by the Glatorian system. The Toa later rebuilt a New Atero, in the forest north of the Black Spike Mountains.
The area formerly ruled by the Elemental Lord of Sand: a huge desert in the central region of Spherus Magna. It is home to the Sand tribe. A large group of the Agori and Glatorian were here when the Shattering of Spherus Magna occurred.