Mavrah was an Onu-Matoran who lived in Metru Nui.
Mavrah once worked on Metru Nui in the Onu-Metru district. He worked as an archivist who specialised in the area of aquatic Rahi. He was known to have conducted experiments involving Kinloka due to his theory that the Bohrok were living organisms which that had, at some stage, evolved into mechanical entities. Mavrah was also followed the Kanohi Dragon through the lower levels of the Archives at the second time that it awoke and attacked Metru Nui.
When several ancient Rahi were found off the coast of Metru-Nui, Mavrah was selected to oversea them. He did this under orders of Turaga Dume and was helped by Whenua and Onepu. After Mavrah saved Whenua's life in an accident involvig the Rahi. When Dume heard of the impact the escape attempt had taken on the rest of the Archives he shut the project down and ordered the containment of the Rahi so they could ither be killed or released. However, Mavrah managed to steal the Rahi and hide with them beneath the Great Barrier.
Mavrah lived in peace with the Rahi until the Toa Metru attempted to travel through his area in search of Mata Nui. He had them captured then brought to him. When they managed to escape from him he had his Rahi attack them. Several Vahki Rorzakh also attempted to battle to Toa but failed.
During this battle, Onewa was knocked unconsious and fell into the water. Whenua then attempted to save his fellow Toa but ended up knocking himself out in the process of returning to the surface with the Toa of Stone. Onewa then regained his consiousness and blamed Mavrah for Whenua's suffering. The compelled Mavrah to stop the battle but he ended up being knocked into the water. Mavrah, however, survived this ordeal and was transported to the Red Star. Much later, he encountered the Toa Nuva Kopaka and Pohatu, and emerged from one of the rooms within the Red Star to rescue them.
- BIONICLE Legends 4: Legacy of Evil - First Chronological Appearance
- BIONICLE Adventures 5: Voyage of Fear - First Appearance
- BIONICLE Adventures 6: Maze of Shadows - Mentioned
- BIONICLE Legends 10: Swamp of Secrets - Mentioned
- BIONICLE Encyclopedia Volume 1 - Mentioned
- BIONICLE Encyclopedia Volume 2 - Mentioned
- The Powers that Be