This timeline is based on items from official sources; particularly mini-timelines in LEGO Club Magazine and BIONICLE World (see References section below for details). These are supported by statements from series writer Greg Farshtey on the BZPower fan forum.
Over 100,000 Years Before the Great Cataclysm
- Great Beings create universe, starting with the Matoran. Artakha is the first location created.
- Exceptionally good- or bad-working Matoran sent to other lands: Good to Artakha permanently, bad to Karzahni "temporarily".
- Some badly-repaired Matoran sent from Karzahni to Mount Valmai, rest kept in realm.
- Mask of Life created and hidden under Mount Valmai by Great Beings.
- Sending of Matoran to Karzahni stops.
- First Toa and Rahi (specifically, giant sea beasts) also created during this time.
The Time Before Time
Around 100,000 Years Before the Great Cataclysm
- Great Spirit Mata Nui sent by Great Beings to protect universe.
- Makuta species created, organizing themselves as a Brotherhood.
- First team of Toa assembled, and the Bohrok are created.
- Metru Nui built and populated.
- Great Beings depart for other universes.
94,000 Years Before the Great Cataclysm
- Mata Nui creates six Barraki warlords. Barraki conquer most of the world.
93,000 Years Before the Great Cataclysm
- Barraki form military alliance called League of Six Kingdoms.
89,000 Years Before the Great Cataclysm
- Toa Mata created by this time.
86,000 Years Before the Great Cataclysm
- Metru Nui forges trade pact with League of Six Kingdoms.
Sometime over 79,000 Years Before the Great Cataclysm
- Kanohi Dragon defeated by Toa and imprisoned in ice under unknown circumstances.
79,000 Years Before the Great Cataclysm
- League of Six Kingdoms plots to usurp Mata Nui. Brotherhood of Makuta learns of their plans, allies with the Toa to launch preemptive strike. Barraki are captured; Order of Mata Nui intervenes and banishes them to the Pit. League's trade pacts are made void and trade is disrupted.
78,500 - 78,100 Years Before the Great Cataclysm
- Great Disruption. Metru Nui enters civil war, halting normal work. Brotherhood of Makuta steps in and ends fighting. Order of Mata Nui banishes war leaders to the Pit; places an agent in Metru Nui.
- Toa Jovan leads his team to Mount Valmai and the Mask of Life. Jovan later becomes a Turaga and leads the region's Matoran.
74,000 Years Before the Great Cataclysm
- A Brotherhood member arrives on Zakaz and begins tampering with the native Skakdi.
59,000 Years Before the Great Cataclysm
- Time Slip. Six-month period of which no memories or records exist outside of Order of Mata Nui. Order scatters several disguised Av-Matoran among many lands, including Takua in Metru Nui.
15,000 Years Before the Great Cataclysm
14,000 Years Before the Great Cataclysm
- Turaga Dume appointed as leader of Metru Nui.
6,005 Years Before the Great Cataclysm
- Lhikan becomes a Toa of Fire.
6,000 Years Before the Great Cataclysm
- Two Skakdi, Vezok and Hakann, steal the Makoki stone from a Toa fortress. They are caught and recruited into the Dark Hunters. (The other four Skakdi who would become Piraka were recruited prior to this time.) The day after the theft, the Toa fortress is overrun by Frostelus, leaving Lhikan as the only survivor.
- Even at this point, the Brotherhood has begun to be corrupted, as the Toa are suspicious and gathering information on them.
- Sidorak is rejected by the Dark Hunters; he eventually gains a position with the Brotherhood of Makuta.
4,000 Years Before the Great Cataclysm
- Zaktan leads rebellion against the Shadowed One, but fails. Shadowed One tries to execute him, but Zaktan survives as a mass of protodites.
Sometime over 3,000 Years Before the Great Cataclysm
- Nuparu invents machines to enforce order in Metru Nui. The Kralhi is a failure, but the Vahki design is successful and is quickly put to use.
3,000 Years Before the Great Cataclysm
- Dark Hunters release Kanohi Dragon to attack Metru Nui. Eleven Toa, including Lhikan and Nidhiki, come to Metru Nui to fight it.
- After a month of fighting, the Toa win and deport the Kanohi Dragon to Xia. They stay as the city's resident Toa afterwards.
2,000 Years Before the Great Cataclysm
- The Shadowed One declares war on Metru Nui. Hundreds of Toa come to the city's defense.
- War ends months later when Nidhiki betrays Toa and helps set a trap, but Lhikan finds out and sets his own that snares the Hunters. Makoki stone given to Toa in exchange for Hunters' freedom. Dark Hunters and Nidhiki banished from Metru Nui.
- Nidhiki joins the Dark Hunters and trains them. He eventually is paired with Krekka and sent on missions himself.
- Six months after the end of the war, Roodaka comes to the Dark Hunters for training; "buys" it by horribly mutating the traitorous Nidhiki.
- The Shadowed One has the Makoki stone stolen back, split into six, and auctioned off to the Brotherhood of Makuta.
1,900 Years Before the Great Cataclysm
- Roodaka employed by the Brotherhood of Makuta.
Sometime over 300 Years Before the Great Cataclysm
300 Years Before the Great Cataclysm
- Toa Hagah learn of the Brotherhood's corruption and rebel, stealing the Mask of Light from them.
- Makuta attacks Mata Nui, leaving him badly injured.
- Toa Hagah captured and mutated into Rahaga by Roodaka. Sidorak claims credit for Rahaga; Brotherhood gives control of Visorak hordes to him with Roodaka as second-in-command.
- Visorak begin to conquer every land they can find. Rahaga begin working to undermine Visorak's conquests.
50 Years Before the Great Cataclysm:
- Rahaga arrive in Metru Nui and hide the Mask of Light.
Unknown Times Before the Great Cataclysm:
- Sidorak betrays his clan leader to the Brotherhood; the leader is mutated into Voporak.
- Order of Mata Nui sends Axonn and Brutaka to guard the Mask of Life, in addition to Umbra.
Fall of Metru Nui
The Great Shadow
18 Months Before the Great Cataclysm
- Makuta secretly captures and impersonates Turaga Dume and takes his place.
- Makuta creates the Karzahni plant monster; but the Karzahni is too powerful and ambitious so he creates a weaker version and calls it the Morbuzakh. He also hires Dark Hunters to help.
- "Dume" orders all passages to and from Metru Nui sealed off. The Toa sent on these and other missions are killed one by one until only Lhikan is left.
Around 1 Year Before the Great Cataclysm
- The Morbuzakh is unleashed and begins to kidnap Matoran and cause property damage. The rest of the population to evacuate towards the city's center.
- Lhikan becomes suspicious of "Dume" and begins to investigate.
A Few Weeks Before the Great Cataclysm
- Lhikan chooses six Matoran and gives them Toa stones. He is captured upon delivering the final one.
- The Toa stones transform the Matoran into Toa Metru. Toa Vakama receives a vision telling him to find the Great Kanoka Disks.
- Toa Metru search for the Matoran that know the Disks' locations, then for the Disks themselves.
- Toa Metru destroy the Morbuzakh using the Great Disks.
- Toa Metru face Krahka, waking a Tahtorak in the process.
- Despite the Morbuzakh's defeat, Matoran continue to disappear.
The Great Cataclysm
- "Dume" orders arrest of Toa Metru. Three are captured and locked up with a Turaga.
- Imprisoned Toa Metru escape; join free ones. Turaga revealed to be Lhikan.
- Great Spirit Mata Nui falls asleep, leading to the Great Cataclysm:
- Metru Nui hit by earthquake and double eclipse, reducing the city to ruins. Quake also breaks many of the Archives' stasis tubes, freeing the Rahi inside.
- On the planet's surface above Metru Nui, energized protodermis transforms a barren island into a lush tropical paradise.
- Mount Valmai and the surrounding region breaks off of its landmass and rockets up to the surface, becoming the floating island known as Voya Nui. Turaga Jovan killed in the process. Resulting holes above and below Voya Nui's former location cause a waterfall to spill into Karda Nui.
- The dome surrounding the Pit shatters, causing the sea to flood in. The waters mutate the inhabitants into water-breathers, keeping them from escaping outside the ocean.
- Brotherhood of Makuta's corruption exposed worldwide.
- Makuta transforms from his Dume form; absorbing the Dark Hunters into his body.
- Toa Metru confront Makuta. Mask of Time created; lost in sea. Turaga Lhikan killed. Makuta sealed in solid protodermis.
Days After the Great Cataclysm
- Toa Metru arrive at the newly transformed tropical island; name it Mata Nui.
The Great Rescue
Within a Week After the Great Cataclysm
Within a Month After the Great Cataclysm
- Toa Metru return to Metru Nui; are captured by Visorak and mutated into Toa Hordika but saved from death by Rahaga.
- Toa Hordika and Rahaga gather supplies from Visorak-infested city.
- Krahka and Tahtorak join with Toa and Rahaga to fight Visorak; disappear into Zone of Darkness.
- Toa Hordika recover Mask of Light.
- Turaga Dume freed.
- Toa Vakama joins Visorak armies; captures Rahaga. Rest of Toa Hordika find Keetongu.
- Toa Hordika and Keetongu assault Visorak. Vakama rejoins Toa. Rahaga freed. Sidorak killed by Keetongu. Visorak disbanded. Makuta freed; teleports Roodaka away.
- Keetongu restores Toa Hordika into Toa Metru. Toa Metru bring Matoran to island of Mata Nui.
- Toa Vakama recovers Mask of Time; fights with Makuta and Dark Hunters over it. Brotherhood of Makuta/Dark Hunter war starts over Makuta's previous murder of Dark Hunters.
- Toa Metru become Turaga; lead Matoran in building villages on Mata Nui.
Thousand Years of Shadow
0 - 1000 Years After the Great Cataclysm
- Brotherhood of Makuta/Dark Hunter War. Roodaka plays both sides in the conflict. Toa take advantage to strike the Brotherhood when they can.
- Turaga Dume, Rahaga, and Keetongu do what they can to rebuild Metru Nui. Rahaga and Keetongu are away from the city frequently to help Visorak-conquered lands.
- Matoran on Mata Nui begin to physically weaken; they also lose all memory of Metru Nui. Turaga decide to keep Metru Nui's existence a secret.
- Makuta recovers Ahkmou; convinces the Matoran to be his ally.
One Year After the Great Cataclysm:
- Makuta starts to enslave Rahi by having Kraata infect their Kanohi Masks. He commands the enslaved Rahi to attack the Matoran, but the Matoran steadfastly defend themselves. Turaga secretly hunt and capture every Kraata they can find.
100 Years After the Great Cataclysm:
- Matoran of Voya Nui build city of Mahri Nui.
700 Years After the Great Cataclysm:
- Mahri Nui sinks under the sea and close to the Pit; Matoran survive, albeit mutated some.
750 Years After the Great Cataclysm:
- Zaktan discovers the Brotherhood's master plan.
The Fight for Mata Nui
1,000 Years After the Great Cataclysm
- Turaga of Mata Nui captured by Makuta's Rahi.
- Takua rescues Turaga, collects the island's Toa stones. Stones used to summon Toa Mata to island.
- Toa search Mata Nui and each collect a set of twelve Kanohi Masks.
- Toa confront Makuta. Makuta retreats.
- Makuta awakens Bohrok swarms. Bohrok begin to ravage Mata Nui.
- Toa Mata begin collecting Krana from Bohrok.
- All of Le-Koro enslaved by Krana, including Toa Lewa.
- Nuparu invents Boxor defense vehicle.
- Onu-Koro uses Boxors to free Le-Koro.
- Toa Mata enter Bohrok nest, use collected Krana to unlock Exo-Toa armor.
- Toa face Bahrag and seal them in protodermis cage; transformed into Toa Nuva. Bohrok rendered dormant.
- Turaga Vakama loans Mask of Time to Toa Tahu.
- Bohrok-Kal released; steal Nuva Symbols.
- Bohrok ordered back to nests by Bohrok-Kal.
- Bohrok-Kal find Bahrag prison with Toa Nuva in pursuit.
- Toa Nuva use Nuva Symbols to empower Bohrok-Kal; Kal destroyed by power overloads.
- Turaga declare kolhii tournament to celebrate peace.
- Takua finds Mask of Light. Takua and Jaller assigned to find Toa of Light.
- Makuta releases Rahkshi.
- Rahkshi destroy Ta-Koro in pursuit of Mask of Light.
- Rahkshi fight Toa Nuva at Kini-Nui Temple. Jaller sacrifices himself to save Takua. Takua becomes Toa Takanuva. Rahkshi destroyed.
- Takanuva challenges Makuta. Both fall into energized protodermis and merge into Takutanuva.
- Takutanuva reopens path to Metru Nui, resurrect Jaller.
- Gate crushes Takutanuva; Toa Takanuva revived.
- Matoran build boats for travel to Metru Nui. Turaga tell tales of their time as Toa Metru.
Around 11.5 Months After the Arrival of the Toa
- Six Skakdi abandon Dark Hunters; call themselves "Piraka".
- Piraka find Makuta's armor; Vezon created. All gain knowledge of Mask of Life on Voya Nui.
Around A Year After the Arrival of the Toa
- Matoran return to Metru Nui.
The Race for the Mask of Life
Island of Doom
Around A Year After the Arrival of the Toa
- Turaga Dume sends Toa Nuva to save Mata Nui's life by finding and using the Mask of Life.
- Piraka arrive on Voya Nui, enslave all but six Matoran.
- Toa Nuva arrive on Voya Nui, captured by Piraka.
- A group of Matoran go from Metru Nui to help Toa Nuva, end up in Karzahni. They escape and arrive on Voya Nui transformed into Toa Inika.
- Toa Inika join unenslaved Matoran and challenge Piraka and Brutaka. Passageway to Mask of Life uncovered.
- Piraka reach Mask of Life to find it guarded by Vezon and Fenrakk; they are defeated.
- Toa Inika reach Vezon and Fenrakk and succeed in claiming the mask. Fenrakk becomes Kardas during fight.
- Brutaka defeated by Axonn; banished to the Pit by Botar.
- Krahka and Tahtorak use one of Brutaka's portals to escape the Zone of Darkness.
- The Matoran find and free Toa Nuva.
- The Mask of Life flies from the Toa Inika into the ocean. Axonn opens a passage for them to follow with the Toa Nuva's blessing.
City of the Lost
- The Mask of Life floats down to the underwater city of Mahri Nui and is claimed by the Matoran. The Barraki reveal their existence and take the mask.
- Vezon and Kardas, no longer cursed, go their separate ways. Kardas later emerges on the surface of Voya Nui and engages in a fight against Tahtorak.
- Toa Lesovikk arrives in the Pit, is attacked by Karzahni.
- Toa Inika arrive in ocean; changed into Toa Mahri by Mask of Life. Mask also changes the Matoran Dekar into a duplicate of Hydraxon.
- Makuta, still alive, possesses Maxilos robot; joins Toa Mahri under "Maxilos" identity.
- Toa Nuva sneak into Metru Nui, find scroll of tasks to accomplish.
- Toa Nuva set out to pursue tasks, first freeing the Bohrok and then going after the Staff of Artakha.
- In pursuit of the staff, the Toa Nuva make Roodaka turn the Rahaga back into Toa Hagah.
- Toa Mahri spark war between Barraki.
- Staff of Artakha stolen by Makuta Icarax, Toa Nuva follow to the realm of Karzahni. Realm destroyed; Icarax escapes with the staff.
- Makuta leads Matoro to remains of Toa Tuyet, and asks him to reanimate her.
- Karzahni attacks Makuta; Makuta destroys Karzahni's mind.
- Icarax gives Staff of Artakha to Makuta. Brutaka intervenes claims it for the Order of Mata Nui.
- Takadox exposed as traitor within Barraki; all Barraki caught up in battle with Toa Mahri, Hydraxon, Maxilos, and a giant Gadunka. Toa Mahri get away with Mask of Life.
- Toa Nuva set off on various tasks; reunited by Order of Mata Nui. Order uses Staff of Artakha to repair Great Cataclysm damage, with exception of Karda Nui.
- Karzahni defeated by Lesovikk and taken into Order custody.
- Matoran of Voya Nui and Mahri Nui evacuate into Voya Nui underground.
- Toa Mahri shatter Voya Nui-Mahri Nui connection, causing island to sink. Toa Mahri follow with Barraki in pursuit.
- Mata Nui dies. Five Toa Mahri make stand to allow Toa Matoro to continue following Voya Nui.
- Matoro enters Karda Nui. Voya Nui settles in original location directly above. Matoro sacrifices himself to revive Mata Nui; teleports other Mahri home to Metru Nui.
The Battle for Karda Nui
- Toa Nuva teleported to Artakha; then to Karda Nui with new armor.
- When Mata Nui is revived, the Makuta in Karda Nui were blinded by the energy given out.
- The Makuta attack the Av-Matoran, converting some of them into Shadow Matoran (to act as their new "eyes"). Some Av-Matoran survive the attack.
- Takanuva is attacked near Metru Nui, but saved by the Order of Mata Nui. Brutaka uses his Kanohi Olmak with the intent of sending Takanuva to Karda Nui, but ends up sending him to the alternate universe ruled by the Toa Empire instead.
General placement of several events can be found in:
- LEGO Club Magazine Brickmaster Edition, March/April 2007 issue
- "Metru Nui" entry, History section; BIONICLE World
- Stated as near Great Disruption in Toa Jovan's Team Mission at BZPower forums
- Official Greg Discussion p. 219 at BZPower forums, post #6557; p. 269 post #8062
- "Brotherhood of Makuta" entry, BIONICLE Encyclopedia Second Edition
- Official Greg Discussion p. 292 post #8733
- Official Greg Discussion p. 206, post #6164
- Dates for founding and sinking of Voya Nui found in Official Greg Discussion p. 259 post #7741
- Official Greg Discussion page 238