* Note: The true timeline and order for the events on this page are especially unclear. Some of these events (especially the things marked XBlaze) may be a part of an alternate timeline. It’s not even clear which century or millennia some of these events happened in. Maybe Central Fiction will clarify things. Just know that I'm doing a lot guesswork for this particular page. *
Age of Origin and other long ago, indeterminate time periods
A long time ago, during the Age of Origin, humanity fights a huge war against a mysterious enemy outside of logic. Humanity creates the weapon Hihiirokane, which can cut spirits. After the war, the Hihiirokane is protected by a clan of cat beastkins hidden in the mountains of Japan. (Phase Shift 1 / 3)
A couple hundred years before the Dark War, humanity fights a smaller scale war against a mysterious enemy outside of logic. Humanity creates the Sealed Weapon Izayoi. Izayoi has two forms. The normal form of Izayoi protects against Phenomenon, the final form can destroy Phenomenon. (Phase Shift 3 / Material Collections)
The "Legacy Weapons" are created to fight beings outside of logic.
The Azure Shrine Maiden (also known as the Amanohokosaka Shrine Maiden) gains the natural ability to communicate with the Azure after finding a Gate in Wadatsumi. One day, the Black Beast somehow comes out of the Gate. She sacrifices herself luring the Black Beast back into the Boundary. The Amanohokosaka Clan dedicates itself over the next thousands of years to watching over Wadatsumi and preventing the Black Beast from ever escaping again. (XBlaze)
At some point, Terumi gains control of Susano'o (and becomes a Black Susano’o), but he eventually abandons the Unit.
Somehow Terumi creates two Azure Grimoires, which either accesses a small portion of the Azure or contains a fake miniature copy of the Boundary and Azure. It’s not clear exactly how the Azure Grimoire works, but it’s very, very powerful.
The Mage's Guild becomes responsible for safeguarding Out of Place Artifacts (powerful excavated artifacts of unknown origin.) These include Izayoi and several Legacy Weapons. (XBlaze)
The Susano'o Unit is discovered in Japan in an ancient location deep underground. This location is referred to as the “First Area” (or "First District" or "District 1.") A Vampire family called the Alucard Clan, led by Clavis Alucard, takes in the Susano'o Unit. (Material Collection)
After digging further in the First Area, a Cauldron is discovered and modern humanity learns about the Boundary.
Humans can't survive in the Boundary, so they develop Artificial Humans called Prime Field Devices. One of these Prime Field Devices discovers the Azure. This causes it to gain a soul and inherit the Eyes of Azure, which gives it access to the power of the Azure. The researchers get freaked out over this and "seal it in the Boundary."
2040s (According to XBlaze)
(Thirteen Years Before XBlaze) A serial killer named Ripper is caught, but escapes transportation to prison after suddenly growing a mysterious Crystal and developing a Drive (making him what's later called an “Irregular Type Union.”) One of the officers transporting Ripper, named Kazuto Kotetsu, manages to survive Ripper's escape and swears to hunt Ripper down. Kazuto eventually allies himself with the Mage's Guild. (XBlaze)
Ripper is able to sense other Unions (humans with Crystals and Drives) and starts to hunt them down. (XBlaze)
The T-System is envisioned to be an advanced AI that can calculate every living thing's thought pattern, predict what will happen, and then use Phenomenon Intervention to choose the best course for humanity. The Takamagahara Organization is a group that is claiming to be developing a new energy source, but is actually trying to create the T-system. The Takamagahara Organization has the cooperation of the Mage's Guild. (XBlaze)
The Amanohokosakas are forced to sell Wadatsumi to the Takamagahara Organization by the Mage's Guild. (XBlaze)
The T-System will require (1) an Embryo in order to perform Phenomenon Interventions and (2) the Original Grimoire to activate the Embryo. The Original Grimoire is said to draw out the Black Beast from the Boundary. The Grimoire can devour souls and turn Seithr into power. The Mage's Guild has the Original Grimoire and gives it to the Takamagahara Organization. A young girl named Hinata is kidnapped at a young age and experimented on to become the Embryo. (XBlaze)
(Ten Years Before XBlaze) Wadatsumi Mass Vanish Incident: The experiment to create the T-System is started at the Takamagahara Wadatsumi Laboratory. The Original Grimoire begins devouring the souls of over 3,000 people in the city. The head of the Takamagahara Wadatsumi Laboratory, Ryoko Kagari, has opposed the project since its inception and sacrifices herself to shut down the operation. This results in all the souls being spread out as crystals, leading to the creation of a lot of Drive-Unions. Drive Unions are people who mysteriously grow a Crystal, gain a Drive, and then ultimately go insane before finally dissolving into Seithr. There is a good chance this did not happen in the mainline BlazBlue timelines and the Takamagahara System is successfully created instead. (XBlaze)
The Embryo reverts to a girl named Hinata Himezuru and the Original Grimoire becomes a boy named Touya Kagari. They don't remember their origins, although Hinata unintentionally causes Phenomenon Interventions throughout her life. (XBlaze)
In 2045, Soichiro Unomaru, a Takamagahara scientist, creates Es as a vessel for the Embryo, but it's a failure. He realizes Es seems to have a personality and soul. Unomaru uses her as his personal soldier. He ends up creating nine other Es-like beings, called Es-N. (XBlaze)
A mysterious international agency, called the Mitsurugi Agency, takes it upon themselves to study and try to heal Unions. The Agency is a Private Military Company and has considerable strength. (XBlaze)
Unomaru places the blame for the Wadatsumi Mass Vanish Incident on Ryoko Kagari. Unomaru becomes the director of the Mitsurugi Agency's Seventh Laboratory branch in Shin-Yokohama. Among his subordinates are Es, the Es-N units, and Mei Amanohokosaka. He's secretly collecting the Drive-Union's crystals to activate the T-System. Under the name TC, he develops the popular social application TOi as a T-System proof of concept. (XBlaze)
(Six Years Before XBlaze) Ten Sage Zwei gives up her title and goes into hiding as Ringo Akagi. (XBlaze)
Ten Sage Sechs speaks with a mysterious crystal and begins to wish for the destruction of the world. Sechs learns that he's an artificial being and decides that because he's not human, he can perform the inhumane act of reducing everything to nothing in order to remove all suffering from the world. He plans to flood the world with Seithr to force everything back to the Boundary/Azure, making existence perfect, eternal, and in harmony. He recruits Ten Sages Drei and Acht and then defects from the Mage's Guild. He steals the Legacy Weapon Sword of Destruction: Kusanagi, which makes him stronger every time Phenomenon Intervention is used, but makes his existence shared across timelines. (XBlaze)
2050s (According to XBlaze. Everything that happens as a result of the Wadatsumi Mass Vanish Incident is probably from an alternate timeline to the mainline BlazBlue games)
The Mage's Guild is actively hunting down the renegade mages Sechs, Drei, and Acht. Kazuto, now going as Avenge, and Sechs's sister Kuon are independently tasked with assassinating the rogue Sages. (XBlaze)
The cast of XBlaze get wrapped up in Unomaru's plot to activate the T-System and Sech's plot to destroy the world. Touya gradually learns the secrets of his origin. (XBlaze)
Kazuto kills Ripper after Touya drains all of Ripper's Seithr. Kazuto later kills Drei. Kuon (with Mei Amanohokosaka's help) kills Acht. (XBlaze)
Unomaru reveals himself as the orchestrator of Wadatsumi Event, but Sechs throws Unomaru into the Boundary before he’s able to activate the T-System. Sechs throws Hinata and Es into the Boundary, where Es is able to take the Embryo for herself. Using the Embryo, she temporarily sends Touya to the original timeline where Hinata made no Phenomenon Interventions. Without any Phenomenon Interventions boosting up his Kusanagi, Sechs is weak and Touya easily kills him with Es's Legacy Weapon: Murakumo. Because Sechs's Legacy Weapon: Kusanagi makes its user the same throughout all realities, all Sechses die. Es stays behind in the Boundary to use the Embryo (a cystallization of the Azure) to protect her world and wipes herself from the memories of all her friends. (XBlaze)
Es creates the World of the Tsukuyomi, which would later become the Phantom Field, to seal the XBlaze world from the rest of the Boundary. This act drains most of the Embryo. (XBlaze)
Vampire Incident: The Mage’s Guild tries to revive Ripper's corpse, but without Ripper's soul, resulting in the timid person named Kiri. Ripper's soul finds a way to communicate with Kiri via a stuffed doll. Ripper eventually tricks Kiri into fusing with him, resulting in 'Freaks.' Es meets a young Nine in Tsukuyomi and they recharge the Embryo, which Es uses to recreate herself as a human and return to her world, where she helps Touya and friends kill Ripper. Kiri is allowed to exist as himself. (XBlaze: Lost Memories)
Mei, the last Es-N (Nu), Es, and Touya dedicate themselves to properly healing the remaining Drive-Unions. They create a new organization to find and destroy all the Cauldrons and prevent anything like Unomaru's plan from happening again. Touya destroys the Wadatsumi Gate. (XBlaze: Lost Memories)
Kuon becomes a Ten Sage, possibly its leader. Marcelyn F. Mercury (Ringo Akagi) becomes the Ten Sage Zwei (again.) (XBlaze: Lost Memories)
Mei Amanohokosaka becomes the leader of the Amanohokosaka clan.
2050s to 2099
Using the data obtained from the First Prime Field Device, humanity creates the AI controlled Takamagahara System to manage the Boundary. Takamagahara is humanity’s attempt to create a Master Unit, but Takamagahara is far inferior to the Master Unit. Takamagahara can rewind major events, but the Master Unit can rewind any event. (Material Collection)
Humanity tries to weaponize the Azure. Special weaponized Prime Field Devices, called Murakumo Units, are created to obtain the Azure. These units are based off of Izayoi. The Murakumo Units are designed to have sealed personalities and sealed emotions so that they can be controlled after gaining the Eye of Azure. If a Murakumo Unit is able to gain the power of the Azure, it is designated as a Kusanagi. No Kusanagi are successfully created in this era. (Material Collection)
In an attempt to take over her clan, Saya Terumi kills everyone in her clan except for her mother and brother (Naoto 'Kurogane', the proper heir.) Mei Amanohokosaka captures Saya and is able to detain her for five years. (Bloodedge Experience)
(Two years before Bloodedge Experience) Clavis kills someone who was possessed by the Soul Eater Drive and finds an Embryo that becomes a girl named Raquel. Clavis adopts her into his family. (Bloodedge Experience)
Naoto Kurogane loses his right arm and gets mortally wounded saving Raquel from one of Spinner Superior's Apostles. Raquel makes a contract with him to save him by biting him, turning him into a vampire that feeds off her life force in exchange for him helping her to find the Azure. Raquel also makes a new arm for Naoto out her own blood. (Bloodedge Experience)
Relius Clover (a genius alchemist) and Valkenhayn (a werewolf created with Sorcery) are hired as 'Immortal Breakers' by the Mitsurugi Agency to kill Clavis Alucard. They fail and Valkenhayn eventually ends up serving Clavis. (Bloodedge Experience)
Naoto loses his left arm and right leg fighting Spinner. Relius makes him artificial replacements. (Bloodedge Experience)
Konoe M. Mercury is born with the ability to attract Seithr and Celica M. Mercury is born with the power to suppress Seithr. Their father, a genius scientist named Shuichiro Ayatsuki, creates a replica of the Original Grimoire to safely absorb the Seithr Konoe attracts. (XBlaze: Lost Memories)
As a young mage, Konoe wanders into the Boundary and encounters Es from the Vampire Incident timeframe. She uses her Original Grimoire to help repower Es's Embryo. (XBlaze: Lost Memories)
Relius Clover and Shuichiro Ayatsuki begin collaborating to understand the Boundary. They get stuck until Terumi appears with valuable information. He agrees to help them under the condition that they help him create a Kusanagi.
In 2099, Terumi, Relius, and Shuichiro attempt to create a Kusanagi. During an experiment, Terumi loses his current physical body and damages his spiritual body. Relius creates an artificial body that Terumi can use once his spiritual body heals. Relius sends the sentient body, Kazuma Kval, to Ishana as a student. (Phase Shift 1)