Onu-Koro (Mata Nui)

"Another enormous cavern lay before him, lit by more Lightstone platforms. Dozens of stone columns stretched up to the high ceiling. Between these columns were paths made of cobblestones set into the earthen floor. Stone benches stood beside the paths, and a small, clear stream trickled through the cavern."

- Narrator, Tale of the Toa

Onu-Koro was the village of Earth on the Isle of Mata Nui.

History
The undercity of Onu-Koro was discovered and founded by Toa Whenua after the Toa Metru defeated Makuta Teridax and left Metru Nui to search for a new home for the Matoran. It was constructed by the Onu-Matoran under the direction of Whenua, from pieces of the dismantled Airships used in the Great Rescue.

The Matoran and newly transformed Turaga Whenua dwelt in Onu-Koro for one thousand years, always having to cope with the constant Rahi attacks unleashed by Teridax, and clinging to the hope of the Toa Mata coming to save them. Around the time the Toa arrived on Mata Nui, an impenetrable layer of rock was unearthed in the Great Mine, impeding the Miners. In addition to that, many problems were brought up; a lava flow blocked the path to the Cavern of Light, leading to a shortage of Lightstones, and, because of this, Rahi attacks increased. Takua helped solved these problems, and later discovered that the impenetrable layer of rock was a sundial, concealing a secret entrance to the Mangaia. The village was barred in preparation for battle with Rahi as the Toa battled Teridax.

After the Bohrok were awakened and started to level the island, Nuhvok attacked the village, trying to destroy columns in a cavern, in an attempt to cave Onu-Koro in. However, Onua was able to trick them into retreat by using their assignment against them and creating a trench around one of the last columns. Shortly afterward it was attacked and flooded by Gahlok, but Nuparu helped drive them off with his new invention, the Boxor. The flood halted much work, and, up to the leaving of the Matoran, remained flooded.

Following the Toa Mata's transformation into Toa Nuva, Onua's Nuva Symbol appeared in Onu-Koro. Shortly afterwards, it was stolen by a Bohrok-Kal, stripping Onua of his Elemental Powers. The Nuva Symbol was returned to the village after the Bohrok-Kal were defeated by the Toa Nuva.

The village was later severely damaged by the Rahkshi Turahk, Kurahk, and Vorahk, and was deserted by the Matoran when they returned to Metru Nui. It was later destroyed by the reawakened Bohrok swarms and the location wiped from existence by Mata Nui's awakening.

Landscape
Onu-Koro was located in Onu-Wahi and was made up of the underground caves of the Wahi, with very little of it being on the surface. A landmark nearby was the Papa Nihu Reef. Underground, there was a labyrinth of tunnels leading to different locations, with Lightstones as the Onu-Matoran's source of light. These Matoran are sensitive to daylight, so they worked as Miners or Engineers. Their Turaga is Turaga Whenua, who looks after and instructs the Matoran villagers here. The Rahi here were mostly nocturnal, and some creatures looked like the crustaceans and arachnids of Earth. A sport played here was the Great Ussal Race, a sport involving riding Ussal crabs.

There were entrances leading to Onu-Wahi from Le-Wahi, Po-Wahi, and Ko-Wahi. These entrances were all tunnels dug by the Onu-Matoran.

Ussal Crab Stables
The Ussal Crab Stables were stables where tamed Ussal Crabs rested and were treated while on Mata Nui. The Ussal Crabs and Matoran have since returned to Metru Nui and the stables were destroyed by the reawakened Bohrok swarms.

Onu-Matoran
Onu-Matoran were the primary residents of Onu-Koro. Here, the Matoran performed day-to-day activities which mainly consisted of mining and digging.

Former Notable Inhabitants

 * Whenua: Turaga of Onu-Koro and their leader.
 * Onepu: Head of the Ussalry and Kolhii player.
 * Taipu: Very strong miner and a member of the Chronicler's Company.
 * Nuparu: An inventor who invented the Boxor and helped fight the Bohrok, and former Toa Inika and now Toa Mahri.
 * Onua: Toa Mata turned Toa Nuva of Earth.

Quotes
"Onu-Koro is home to Turaga Whenua. This village consists of huge caves are dug deep underground, safely hidden from the surface. Like its Toa, Onua, the people of Onu-Koru have night vision, but are sensitive to daylight. Some say that Onu-Koro is as dark as the Makuta would wish it, and care should be taken when entering this labyrinth of tunnels and caves."

- BIONICLE.com

Appearances

 * BIONICLE Chronicles 1: Tale of the Toa
 * BIONICLE Chronicles 2: Beware the Bohrok
 * Wall of History (BIONICLE.com) (Mentioned Only)
 * Comic 14: At Last -- Takanuva! (Mentioned Only)
 * BIONICLE: Mask of Light
 * BIONICLE: Mask of Light (Book)
 * The Legend Continues
 * BIONICLE: The Official Guide to BIONICLE
 * BIONICLE: Encyclopedia (Mentioned Only)
 * BIONICLE: Encyclopedia Updated (Mentioned Only)
 * BIONICLE: Quest for the Toa
 * Mata Nui Online Game
 * BIONICLE: Quest for the Masks (Non-canonical Appearance)
 * Bohrok Online Animations
 * Mata Nui Explorer (2002)
 * Toa Nuva Promo CD
 * Mata Nui Online Game II: The Final Chronicle
 * BIONICLE: The Game (Non-canonical Appearance)
 * BIONICLE: Mask of Light Game (Non-canonical Appearance)
 * Mata Nui Explorer (2003)
 * Mata Nui Explorer (Movie)