Six heroes began a quest on the island paradise of Mata Nui. The Toa – biomechanical beings who command elemental powers – found themselves banding together to help the island’s inhabitants: Matoran villagers and their Turaga elders. Golden Kanohi masks of power helped the Toa tame rahi beasts that had been turned to evil by the Makuta, a dark and mysterious being who wove dark plots in his lair beneath a volcano.
Together, the six heroes learned to trust one another and learned the meaning of Unity, Duty, and Destiny. Together, Tahu, Gali, Kopaka, Lewa, Pohatu, and Onua used their golden Kanohi to tame the rahi and confront Makuta in his lair. Together, they sent Makuta away from Mata Nui, but before fading Makuta released another blight onto Mata Nui.
The Bohrok Swarms.
Once released from their slumber, these voracious mechanical bugs levelled everything in their path. Inside their curved heads lay rubbery Krana, creatures that used the Bohrok as an exoskeleton. Krana could not only drive a Bohrok, they could act as a mask and take over any form of life – Matoran, Turaga, even Toa, as Lewa discovered.
The Turaga told an ancient tale of the Bohrok: the Toa must collect eight different types of krana from each of the six types of Bohrok in order to defeat the swarms. Despite villages being ravaged, the Toa and Matoran bravely fought the bugs. The Toa discovered a Bohrok nest and placed their Krana into niches within the tunnels, halting the swarm but unleashing Cahdok and Gahdok, the Bahrag twins. They commanded the Swarms. The Toa created an energized protodermis cage which traps the Bahrag, finally halting the swarms.
In their moment of triumph, the Toa are swallowed into pools of energized protodermis, transforming them into the even more powerful Toa Nuva. This new power would help them fight the Bohrok-Kal, backup commanders of the Bohrok in case the Bahrag failed. The Kal unleashed the Bohrok Swarms once again, and stole the mysterious Nuva symbols which now contained the Toa Nuva’s elemental powers. The Kal planned to use the stone symbols to form a Nuva cube, which would free the Bahrag, but the Toa tricked the Kal and fed their energies into the symbols. The greedy Kal, thinking to rule along with the Bahrag, destroyed themselves. The swarms were stopped once more.
After the Matoran rebuild shattered villages, a Matoran named Takua found a mysterious Kanohi mask: the Mask of Light. He and the Captain of the Ta-Koro guard, Jaller, are tasked with searching for the heralded Seventh Toa. Deadly Rahkshi creatures are sent by Makuta, who has returned to Mata Nui, to stop the two Matoran. Their journeys reveal that Takua is meant to be the seventh Toa, and he dons the mask, becoming Takanuva, Toa of Light. Takanuva battles Makuta in his dark lair and vanquishes the dark menace, in the process leading everyone to rediscover the lost city of Metru Nui.
The Turaga elders decide it’s time to tell of that ancient city, the City of Legends. A thousand years before, Metru Nui was full of life and bustle, before the coming of the Morbuzahk. This nasty vine being wreaked havoc on the metropolis, under the control of Makuta, who was disguised as that city’s Turaga. The lone Toa of Metru Nui, Toa Lhikan, helps transform six Matoran into Toa Metru. These Toa would later become the Turaga elders of Mata Nui, but as Toa they tracked the Morbuzahk to the great furnace in Ta-Metru and defeated it with Great Kanoka Disks they’d collected.
The six Toa heroes, far from being thanked for their work, are called impostors by the fake Turaga Dume, and are forced to evade both mechanical Vahki peacekeepers and Dark Hunters. The Toa Metru discover Makuta is impersonating Turaga Dume, who orders all Matoran to be placed into pods and put to sleep. This sends the Great Spirit Mata Nui into a deep sleep as well. After imprisoning Makuta in a shell of Protodermis using a special Mask of Time, the Toa Metru attempt to retrieve the Matoran pods.
But they are stopped by the spidery Visorak. Venom transforms the Toa Metru into Toa Hordika, half-beasts who must search for the legendary Rahi Keetongu to free them from being Hordika. In doing so, the great city is greatly damaged. Finally restored to their Metru forms, the six Toa bring the Matoran pods up to the newly-discovered island paradise of Mata Nui and awaken them. The heroes give up their powers to become Turaga, and don’t tell the newly awakened and confused Matoran of their past.
The Turaga finish their tale of Metru Nui, and the inhabitants of Swarm-ravaged Mata Nui decide to go back to Metru Nui. But once there, they discover the Great Spirit Mata Nui isn’t just sleeping – he’s dying. The Toa Nuva must find the floating island of Voya Nui and retrieve the Kanohi Ignika, the Mask of Life, guarded by fearsome warriors. But they’ve been beaten to it by six nasty creatures who call themselves Piraka. The Piraka have fooled the Matoran of Voya Nui into thinking they are actually Toa. The Piraka are after the Mask of Life too. But they didn’t count on six new heroes created from Matoran, the Toa Inika, challenging their plans.
Only the scheming and backstabbing actions of the Piraka keep them from getting their claws on the Mask of Life before it plummets into the deep ocean. At the bottom of the ocean lies another city, Mahri Nui, broken off the main island of Voya Nui long ago. Surrounded by air bubbles, Mahri Nui’s survival is precarious. It’s right next to The Pit, where undesirables have been sent for millennia to be punished.
The Barraki, six warlords who were hideously transformed when sent to the Pit, fight over the Mask of Life to restore themselves to power. But they are denied their prize when the Toa Inika journey to Mahri Nui and are transformed into water-breathing Toa Mahri by the Mask of Life itself. After battling many creeps from the deep, including their old nemesis Makuta in a robotic form, Toa Matoro finally wins the mask. They destroy the stone cord linking Voya Nui with Mahri Nui, plunging Voya Nui down to plug a hole in the World That Feeds The World, Karda Nui. But they aren’t in time.
The Great Spirit Mata Nui died.
Faced with the destruction of the universe, Matoro places the Mask of Life on his face, and chooses to sacrifice himself to save the Great Spirit and his friends. The massive energies from the Ignika bring Mata Nui back to life, but still in a dangerous sleep. There’s only one place where the Toa Nuva can wake Mata Nui, so they are transported to a massive cave, where they find Matoran of Light battling winged Makuta in the mists of Karda Nui.
In the toxic swamp at the bottom of Karda Nui, the Toa Nuva fight for the Mask of Life and search for ways to enter a mysterious metallic dome buried in a fallen stalactite. But even with the help of the silent Toa Ignika, the Toa Nuva must battle mutated Makuta to waken Mata Nui.