The Great Barrier

The Great Barrier was the incredibly huge underground dome of rock and solid ProtodermisProtodermisThe engineered substance building the Matoran Universe, protodermis exists in countless refined states from mundane metal to diamond-hard crystal to the destruction-or-transformation force of energized form. that housed the city of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. and the entire Silver SeaThe Silver SeaThe vast body of unrefined liquid Protodermis surrounding Metru Nui inside the Great Barrier dome of the Matoran Universe.. It formed the outer wall and ceiling of one of the principal domes of the Matoran UniverseMatoran UniverseA civilization of biomechanical beings living inside a colossal robot, destroyed when Teridax seized control., enclosed every notable Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. event of the late pre-Cataclysm period within its shell, and served as the cliff face into which the Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. sealed TeridaxTeridaxTeridax orchestrated a thousand-year scheme that ended with him occupying the Great Spirit Robot itself before his death on Bara Magna. after his coup. When the Great CataclysmThe Great CataclysmThe day Makuta Teridax put the Great Spirit to sleep, the Great Spirit Robot fell from the sky, Metru Nui flooded, and Voya Nui tore loose from the Southern Continent. struck, the dome cracked. The breach was the route by which the Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. carried the sleeping MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. population out of the city and up to the island of Mata NuiMata Nui (Location)An island created by accident on the Great Spirit's face, home to the Matoran for a thousand years., and it remained the principal connection between the two regions for the thousand years that followed.

Structure and scale#

The Great Barrier was a single continuous shell. Its substance was a mixture of rock and solid ProtodermisProtodermisThe engineered substance building the Matoran Universe, protodermis exists in countless refined states from mundane metal to diamond-hard crystal to the destruction-or-transformation force of energized form., the same material that pervaded the Matoran UniverseMatoran UniverseA civilization of biomechanical beings living inside a colossal robot, destroyed when Teridax seized control. in many forms, and the dome was thick enough to contain the entire body of unrefined liquid ProtodermisProtodermisThe engineered substance building the Matoran Universe, protodermis exists in countless refined states from mundane metal to diamond-hard crystal to the destruction-or-transformation force of energized form. that made up the Silver SeaThe Silver SeaThe vast body of unrefined liquid Protodermis surrounding Metru Nui inside the Great Barrier dome of the Matoran Universe.. The city of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. stood at the centre of the cavern that the Barrier defined. The dome formed both the outer wall against which the sea broke and the curved ceiling over the city, and surviving accounts described its inner surface as a sheer cliff face of vast height where it rose out of the water at the southern edge of the sea.

The interior of the dome was concealed from the population it sheltered. Mists obscured the cavern walls, and to a MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. looking up from the streets of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. the ceiling appeared as a normal sky. Two pinpricks of light hung in that false sky, which the city's inhabitants understood as two suns. They were not suns. They were holes in the surface of the body of the Great Spirit, the dome's ceiling functioning as the inner side of the Spirit's face and the two openings serving as the eyes of Mata NuiMata NuiBuilt by the Great Beings to restore Spherus Magna, Mata Nui sustained an entire civilisation inside his body, was deposed by Teridax, and reclaimed his purpose as a mortal on Bara Magna.. A protective barrier sealed each opening so that water and other matter did not pass between the dome and the surface above under ordinary conditions.

The geography of the Matoran UniverseMatoran UniverseA civilization of biomechanical beings living inside a colossal robot, destroyed when Teridax seized control. around the dome was charted in fragments. To the south-east, ships leaving Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. through the main southern sea gate could turn sharply east and follow the curve of the Barrier toward XiaXiaA hostile island southeast of Metru Nui, home to the Vortixx and their brutal mercenary culture.. To the north the dome connected via tunnel and mountain range toward the KarzahniKarzahniA region of the Matoran Universe built by the Great Beings as a Matoran repair facility, ruined by the failures of its overseer. dome. The interior was therefore not entirely closed: the dome had gates, tunnels, and the two ceiling holes long before it was ever cracked.

MavrahMavrahA Metru Nui Archivist who fled his city rather than let Turaga Dume cull his pet sea Rahi, drowned in a feeding frenzy a thousand years before the Great Cataclysm, and was rediscovered alive aboard the Red Star. and the First RahiFirst RahiMassive sea creatures of the Matoran Universe, though specific details remain scarce in canon.#

The Barrier's interior also contained habitable space outside the city itself. After the ArchivesThe Archives of Metru NuiThe Archives of Onu-Metru were the central repository of Matoran knowledge and Rahi specimens, maintained by the Archivist Corps beneath the city's surface. incident that became known as the First RahiFirst RahiMassive sea creatures of the Matoran Universe, though specific details remain scarce in canon. affair, the Onu-MatoranOnu-MatoranEarth-wielding Matoran of the deep who adapted to darkness and built the Matoran Universe's defensive cavalry. MavrahMavrahA Metru Nui Archivist who fled his city rather than let Turaga Dume cull his pet sea Rahi, drowned in a feeding frenzy a thousand years before the Great Cataclysm, and was rediscovered alive aboard the Red Star. was ordered by TuragaTuragaFormer Toa who fulfilled their destiny and transformed into leaders. Turaga wield Noble Kanohi masks and weakened elemental powers, guiding their communities. DumeDumeDume is a Turaga of Fire and the former ruler of Metru Nui, distinguished by his red and black coloring and the Noble Kanohi Kiril, the Mask of Regeneration. As a member of the Turaga of Metru Nui, he wields a Staff of Office and commands a weakened mastery of Fire. He later resides on the reformed Spherus Magna. to remove the captive RahiRahiThe Rahi were the biomechanical wildlife of the Matoran Universe, built largely by the Brotherhood of Makuta, ranging from background fauna to engineered war beasts. from the city. MavrahMavrahA Metru Nui Archivist who fled his city rather than let Turaga Dume cull his pet sea Rahi, drowned in a feeding frenzy a thousand years before the Great Cataclysm, and was rediscovered alive aboard the Red Star. instead led the creatures out of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. and into a river system that lay within the Great Barrier, where he hid them from the authorities and continued his studies in secret. The colony survived in that hidden waterway for hundreds of years.

When the Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. later passed through the same region during their flight from the fallen city, they encountered MavrahMavrahA Metru Nui Archivist who fled his city rather than let Turaga Dume cull his pet sea Rahi, drowned in a feeding frenzy a thousand years before the Great Cataclysm, and was rediscovered alive aboard the Red Star. and his herd of RahiRahiThe Rahi were the biomechanical wildlife of the Matoran Universe, built largely by the Brotherhood of Makuta, ranging from background fauna to engineered war beasts. directly. The Great Undersea RahiRahiThe Rahi were the biomechanical wildlife of the Matoran Universe, built largely by the Brotherhood of Makuta, ranging from background fauna to engineered war beasts. Attack that followed took place inside the Barrier, in waters that connected the Silver SeaThe Silver SeaThe vast body of unrefined liquid Protodermis surrounding Metru Nui inside the Great Barrier dome of the Matoran Universe. to the wider universe beyond. The episode established the dome as a structure with more interior volume than the city alone could account for, and it confirmed that the Silver SeaThe Silver SeaThe vast body of unrefined liquid Protodermis surrounding Metru Nui inside the Great Barrier dome of the Matoran Universe. was joined to a network of subsidiary channels rather than sitting in a single closed bowl.

The Battle of the Great Barrier#

The dome's most famous event was the final battle of the Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety.'s flight from Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive.. After TeridaxTeridaxTeridax orchestrated a thousand-year scheme that ended with him occupying the Great Spirit Robot itself before his death on Bara Magna.'s coup and the absorption of NidhikiNidhikiOnce a guardian of Metru Nui, Nidhiki traded his Toa honor for Dark Hunter gold and paid the price., KrekkaKrekkaA brutish but ineffective Dark Hunter with no powers or masks, Krekka was outmatched from his first moments in Metru Nui., and NivawkNivawkNivawk was a scavenger hawk Rahi that served Makuta Teridax as an aerial spy during his impersonation of Turaga Dume., the MakutaMakuta (Species)Shadowy Antidermis beings and the Brotherhood's elite, Makuta commanded darkness and shaped the Matoran Universe's fate. became a monstrous behemoth and pursued the ToaThe Toa: Heroes of the Matoran UniverseThe Toa were biomechanical guardians sworn to protect the Matoran, bound by a strict code and defined by sacrifice across every age of the universe. across the Silver SeaThe Silver SeaThe vast body of unrefined liquid Protodermis surrounding Metru Nui inside the Great Barrier dome of the Matoran Universe.. The chase ended at the southern wall of the Barrier itself. VakamaVakamaA Ta-Metru maskmaker transformed into the Toa Metru of Fire, leader of his team through the Visorak war, and Turaga of Ta-Koro for a thousand years., now bearing the newly forged Mask of TimeMask of TimeThe Kanohi Vahi is the Matoran Universe's deadliest mask, capable of stopping or accelerating time, and its creation nearly tore Metru Nui apart., confronted TeridaxTeridaxTeridax orchestrated a thousand-year scheme that ended with him occupying the Great Spirit Robot itself before his death on Bara Magna. on the cliff and refused his offer to join the Brotherhood. Using his Mask of Concealment, VakamaVakamaA Ta-Metru maskmaker transformed into the Toa Metru of Fire, leader of his team through the Visorak war, and Turaga of Ta-Koro for a thousand years. tricked the MakutaMakuta (Species)Shadowy Antidermis beings and the Brotherhood's elite, Makuta commanded darkness and shaped the Matoran Universe's fate. into smashing pillars of ProtodermisProtodermisThe engineered substance building the Matoran Universe, protodermis exists in countless refined states from mundane metal to diamond-hard crystal to the destruction-or-transformation force of energized form. into his own body. When TeridaxTeridaxTeridax orchestrated a thousand-year scheme that ended with him occupying the Great Spirit Robot itself before his death on Bara Magna. attempted a final attack, he was crushed against the wall of the Barrier itself.

The Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. then combined their elemental powers and sealed the weakened MakutaMakuta (Species)Shadowy Antidermis beings and the Brotherhood's elite, Makuta commanded darkness and shaped the Matoran Universe's fate. into the cliffside in a Toa SealToa SealA cage of Protodermis created by six Toa combining their Elemental Powers, used to trap powerful beings.: a cage of solid ProtodermisProtodermisThe engineered substance building the Matoran Universe, protodermis exists in countless refined states from mundane metal to diamond-hard crystal to the destruction-or-transformation force of energized form. drawn directly from the dome's own substance. The seal was anchored in the Barrier itself, which meant that the prison was a part of the dome rather than a separate object placed against it. LhikanLhikanToa of Fire, leader of the Toa Mangai, and the last Toa of Metru Nui, who surrendered his Toa Power to create the Toa Metru and died defending Vakama. died in the course of the battle, sacrificing himself to save VakamaVakamaA Ta-Metru maskmaker transformed into the Toa Metru of Fire, leader of his team through the Visorak war, and Turaga of Ta-Koro for a thousand years.. The location of the seal remained an inflection point for the city's later history. Years afterward RoodakaRoodakaShe spent the entire Visorak arc letting everyone think they were using her, then walked away having beaten the Brotherhood and the Toa at their own game. was able to carve a sliver of the seal away with a fingertip and embed the fragment in her armour over her heartstone, which gave her the means to free TeridaxTeridaxTeridax orchestrated a thousand-year scheme that ended with him occupying the Great Spirit Robot itself before his death on Bara Magna. when she eventually shattered the prison.

The breach and the evacuation#

The Great CataclysmThe Great CataclysmThe day Makuta Teridax put the Great Spirit to sleep, the Great Spirit Robot fell from the sky, Metru Nui flooded, and Voya Nui tore loose from the Southern Continent. struck while the Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. were still at the Barrier. The earthquake that flooded Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. also cracked the dome, opening a rift in the structure that had until then been continuous. The ToaThe Toa: Heroes of the Matoran UniverseThe Toa were biomechanical guardians sworn to protect the Matoran, bound by a strict code and defined by sacrifice across every age of the universe. passed through the rift in their hijacked Vahki TransportThe Vahki TransportThe multi-legged cargo vehicle built by the Vahki of Metru Nui and used by the Toa Metru to escape the city across the Silver Sea after the Great Cataclysm., the LhikanLhikanToa of Fire, leader of the Toa Mangai, and the last Toa of Metru Nui, who surrendered his Toa Power to create the Toa Metru and died defending Vakama., carrying six MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. spheres with them. The route led upward through tunnels in the body of the Great Spirit to the new island that had grown on the robot's face, where the Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. deposited the sleepers on the shore at Naho BayNaho BayThe body of water that made up most of Ga-Wahi, named for a fallen Toa of Water and home to the floating village of Ga-Koro on its surface.. VakamaVakamaA Ta-Metru maskmaker transformed into the Toa Metru of Fire, leader of his team through the Visorak war, and Turaga of Ta-Koro for a thousand years. named the island Mata NuiMata Nui (Location)An island created by accident on the Great Spirit's face, home to the Matoran for a thousand years. in honour of the Great Spirit.

The first crossing was followed by a return trip. The Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. sailed back through the rift to recover the remaining MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body., only to be captured and mutated into Toa HordikaToa HordikaToa mutated by Visorak venom into bestial hybrids, forced to fight their primal nature and hunt for a cure. by the VisorakVisorak (Rahi)Spider-like Rahi employed by the Brotherhood of Makuta whose name meant 'Stealers of Life' and whose swarms threatened the Matoran Universe. horde that had moved into the abandoned city. After their later restoration the now-TuragaTuragaFormer Toa who fulfilled their destiny and transformed into leaders. Turaga wield Noble Kanohi masks and weakened elemental powers, guiding their communities. led a final convoy out of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. using six airships built on the streets of Le-MetruLe-MetruThe teal district where Le-Matoran managed everything that moved through Metru Nui, from chutes to airships., and the airships flew through the same rift in the Great Barrier carrying every remaining sleeper. On arrival at the new island the airships were melted down and their material reused in the construction of the six KoroKoroThe Koros were the six elemental villages established by the Toa Metru on Mata Nui after the Great Rescue, each tied to one element and one Turaga.. The breach in the Barrier was therefore travelled in both directions multiple times in the years immediately following the Cataclysm.

Aftermath and use as a portal#

For the thousand years between the Cataclysm and the return migration, the rift in the dome remained the principal physical connection between the dome of Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. and the surface of the island of Mata NuiMata Nui (Location)An island created by accident on the Great Spirit's face, home to the Matoran for a thousand years.. The two ceiling holes that had once served as suns continued to admit light, but their barriers had been disrupted by the Cataclysm and they functioned thereafter as conduits rather than as sealed windows. One was located beneath the waters of Naho BayNaho BayThe body of water that made up most of Ga-Wahi, named for a fallen Toa of Water and home to the floating village of Ga-Koro on its surface., and the other lay under the ice of Mount IhuMount IhuA snow-capped peak in Ko-Wahi where Kopaka sought his first mask and Nuju honored his mentor. on the same island. MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. spheres lost in the original evacuation, debris from the sunken city, and the Cave FishCave FishObscure aquatic Rahi with minimal story presence, documented mostly in BIONICLE creature reference materials. that migrated from the Silver SeaThe Silver SeaThe vast body of unrefined liquid Protodermis surrounding Metru Nui inside the Great Barrier dome of the Matoran Universe. into Aqua MagnaAqua MagnaThe endless ocean where the Matoran Universe found refuge and Mata Nui made his final stand. all moved through these openings in the period after the disaster.

The dome was used as a transit space again at the end of the TuragaTuragaFormer Toa who fulfilled their destiny and transformed into leaders. Turaga wield Noble Kanohi masks and weakened elemental powers, guiding their communities.'s tenure on the island. When the population finally returned to Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive., they descended through the tunnels that the Toa MetruToa Metru and Toa HordikaSix Matoran elevated by Lhikan to save their city, mutated by Visorak venom, and restored in time to deliver the population to safety. had originally travelled in the opposite direction. The arrival reopened the city as a working settlement, and the Barrier resumed its function as the outer wall of a populated environment rather than the boundary of a ruined one.

The Battle of the Great Barrier was also revisited, in a sense, during the events of Time TrapTime TrapVakama's solo descent into the Silver Sea to recover the Mask of Time, his capture by the Dark Hunter Voporak, the Teridax illusion that followed, and the three-way struggle over the Vahi between Vakama, the Shadowed One, and Teridax.. After the recovery of the Mask of TimeMask of TimeThe Kanohi Vahi is the Matoran Universe's deadliest mask, capable of stopping or accelerating time, and its creation nearly tore Metru Nui apart. from the depths of the Silver SeaThe Silver SeaThe vast body of unrefined liquid Protodermis surrounding Metru Nui inside the Great Barrier dome of the Matoran Universe., a waterspout threw VakamaVakamaA Ta-Metru maskmaker transformed into the Toa Metru of Fire, leader of his team through the Visorak war, and Turaga of Ta-Koro for a thousand years. into the Barrier and stunned him long enough for VoporakVoporakVoporak is a mutant member of Sidorak's species and a servant of the Dark Hunters. Clad in dark red, black, orange-yellow, and silver, he wields Rotating Blade Tools and a Rhotuka spinner and commands the power of time. He resides on Spherus Magna. to take the Vahi. The same wall that had served as the anchor for the Toa SealToa SealA cage of Protodermis created by six Toa combining their Elemental Powers, used to trap powerful beings. had become an obstacle in its own right, hard enough to render an experienced Toa unconscious on impact.

Final status#

The Great Barrier remained intact as a structure, though no longer continuous, for the entire remaining lifespan of the Matoran UniverseMatoran UniverseA civilization of biomechanical beings living inside a colossal robot, destroyed when Teridax seized control.. It was still the wall of the Metru NuiMetru NuiThe city beneath Mata Nui functions as the Great Spirit's brain, housing the Matoran whose labor keeps the god alive. dome when TeridaxTeridaxTeridax orchestrated a thousand-year scheme that ended with him occupying the Great Spirit Robot itself before his death on Bara Magna. finally completed his long plan and occupied the body of the Great Spirit Robot, and it was still in place when the Robot was destroyed in the final battle on Bara MagnaBara MagnaA desert world of tribal warfare and scarce resources, one of three landmasses that formed Spherus Magna.. When the Matoran UniverseMatoran UniverseA civilization of biomechanical beings living inside a colossal robot, destroyed when Teridax seized control. was abandoned and its inhabitants migrated to the reformed Spherus MagnaSpherus MagnaA desert world of ancient conflict that became the merger point of the Matoran Universe and Bionicle's true endpoint., the Barrier was left behind along with the city and the sea it had contained. The cliffside seal that had once held TeridaxTeridaxTeridax orchestrated a thousand-year scheme that ended with him occupying the Great Spirit Robot itself before his death on Bara Magna. was by that point a relic of an earlier era, but the wall itself stood as it had since the universe was built, a sheer face of rock and ProtodermisProtodermisThe engineered substance building the Matoran Universe, protodermis exists in countless refined states from mundane metal to diamond-hard crystal to the destruction-or-transformation force of energized form. holding back the dark.