Mata Nui is the Great Spirit of the Bionicle world. He is also a planet. He is best known for doing pretty much nothing in the Bionicle franchise, as he was asleep during much of it.
Name of Mata Nui
The phrase Mata Nui is roughly equivalent to the Boohbahese BOOOOOO BAH. It can mean "come", "go", "stop", or "resume". In addition, it can also represent fear, excitement, resentment, or surprise. The Cheat likes it when you use this phrase.