straight up copypasted from the wiki into WYSIWYG bc i didnt find a rly convenient wikitext to html converter so honestly just look there tbh. But If Not:

Age of the Creators

The era in which the Creators presided over Siderea.

Dawn of Creation

Entirety is created by the High Star and Great Fade.
Some time later they both create Siderea alongside the Vast Glow.
Cetia, Serpentarius, and Librae are created.
The zodiacs are created. Among the initial batch are Mulapin, Graffias, Scorpius, Sariel, Aquari, Sadalsuud, Piscium, and Michael.
Uriel was probably in a very early batch but maybe not the first batch?? idk
Leviathan is born.
Ea is born.
Leonis is born.
Virginis is born.
Tauri and Ishtar are born around the same time.
Capricoris is born.
Cancri is born.
Sagittaria, Orion, and Rigel are born in around the same timeframe.
Arietis is born.
IIRC Betelgeuse was born somewhere during this era??
Metatron, Jophiel, and Sandalphon were probably born in this era as well??

Age of the Gods

The era in which the gods openly reigned.

The Catasterismi

The Great Fade proposes they ascend a pantheon so the High Star can live more happily.
The gods are ascended; Arietis creates the Astral Regalia during her trial.

Divine Era

The gods reign while the Creators continue to watch over, all is well!!
Raziel is born.
The High Star elects to end their life and become part of the reincarnation cycle.
After the High Star is laid to rest, the Great Fade goes off to make Hell College.
The Vast Glow helps support Heaven College some time after but visits Siderea and the High Star's grave frequently.
At some point during or possibly before this era Metatron begins writing the Book of Enoch and Disappearing across space and time, accidentally bringing Sandalphon with them.

Age of the Risen Star

When kity happened. Incredibly short time period, comparatively.

The Risen Star awakens.
The Vast Glow introduces the Risen Star to the gods.
The Risen Star becomes known to Siderean society.
It turns out they are very hungy however.
Scorpius attempts to assassinate the Risen Star but ultimately backs down.
After souls begin to be fed to the Risen Star, Scorpius summons the Great Fade and informs her of the Risen Star's existence.
The Great Fade escorts the Risen Star off of Siderea.

The Great Cetan Exodus

Cetia leaves to find the High Star's halves, initiating the Great Cetan Exodus.
Michael elects to stay behind to carry on Cetia's duties in her absence and receives her Blessing.

Age of Upheaval

The era in which certain horsie boys caused Problems.

The Tragedy of Orion

Orion betrays Sagittaria by tricking her out of Jupiter during a friendly spar and using it against her.
Arietis forges Galaxias for Orion, then takes a Jupiter to the chest. Once Capricoris comes to investigate, Orion strikes her as well.
After targeting Serpentarius, Orion strikes down Tauri, Cancri, and Leonis when they realize something's happened and mount an offensive. Distraught over Leonis, Virginis seeks vengeance and gets struck down as well despite Scorpius explicitly telling him not to.
The remaining gods conspire to trick Orion into believing Scorpius wishes to join him, using illusions and clever shapeshifting to make it seem as though Scorpius has aided him in defeating Geminorum.
Scorpius takes Orion to the Cosmos where they "defeat" Librae and create an opening for Scorpius to use Pluto to pierce the gaps in Orion's armor and eliminate him.
Orion gets Pluto'd in the pancreas and the remaining gods get to yanking the arrows out of the fallen gods and cleaning up the resulting mess.
Not sure how to get rid of it, Galaxias is dismantled and scattered across the planet.
Orion's followers become ostracized, and many of them go into hiding or otherwise flee elsewhere. Betelgeuse ends up off-planet entirely.
The gods rethink their positions and their duties and become considerably less prominent, showing themselves to mortals and granting them power less and less often.
I don't remember if Ganymede was born before or after the whole Orion thing... I feel like I explicitly established the rough era Ganymede was born in but I know at least it wasn't until after the Risen Star thing.
Graffias presumably eclipsed Sariel at some point before this. Whenever that happened, they were around a while longer and made a few attempts at eclipsing Metatron until they no longer needed him and headed offworld, prompting him to change his name to Metatron from Enoch and Disappear far more frequently. On his advice, his sister changed her name as well to Jophiel from Dina, though she wasn't much of a target to begin with. Long since riding in Metatron's head, Sandalphon thought they might as well hop aboard the bandwagon and change their name to Sandalphon from Elijah.

The Vengeance of Rigel

Rigel plots vengeance and goes into hiding, chasing immortality out of fear that his extant immortality from Sagittaria might be revoked. This mostly involves a lot of prima materia chugging and seeking the pieces of Galaxias.
Progressively losing his mind, Rigel vanishes into the earth and isn't heard from for quite a long time.
Chrysomallos, Karkinos, Nemea, Astraea, and Cendrillon are born. Dunno about Artemis, Chiron, Eros, and Asclepius yet; they might be older.
Astraea frees Cendrillon and her peers from their captors.
Rigel eventually returns, crawling out from the core of the planet as a prima materia monstrosity. He begins laying waste to everything around him, doing everything in his power to destabilize the planet itself.
The gods struggle with what to do but ultimately decide they have to lead mortals to save themselves lest they widen the rift between them further.
The gods each pick out champions - including Scorpius picking out a Cetus on Cetia's behalf - and grant them their Blessings, declaring them saints. The saints are also given the Celestial Regalia, forged by Arietis out of anima mundi.
Scorpius and Sagittaria take charge of training the saints, and eventually they have a climactic showdown with Rigel.
Rigel is stopped, but what exactly does that mean? Did he get Pluto'd in the pancreas? Perhaps Hades'd in the head? Normal killed? Redeemed? Uncorrupted and then died from having no body left? Is he still alive out there somewhere? It is a mystery...
Either way the day wasn't exactly yet saved and the next many years were marked by an immense amount of corruption and constant monster outbreaks due to the sheer amount of raw prima materia flowing on the surface thanks to Rigel's actions.
The Archangels probably started being a thing during this era or maybe after Orion. Mayyyybe before?? Idk. This is the most likely event Michael would have died during, and Gabriel likely rose to prominence and died from warning people about monster outbreaks and waves of corruption. If so, then Raphael and Azrael were born before this point and, alongside Uriel, likely died in the aftermath trying to protect people.
I should really mention to that it was like. A LONG time. So long that Siderean society began to adjust to the presence of corruption in their everyday life, likely contributing to the next era out of a desire to understand it all.

Age of Hubris

Ya like manmade apocalypses? This age had a lot of those.

The End of Magic

Mortals begin researching prima materia in-depth to better defend themselves against it and understand the world they live in.
Due to the nature of prima materia, this didn't go particularly well and the most "successful" efforts only seemed to explain it away. People began taking advantage of this discovered property, learning to get meta to combat prima materia.
The excitement over this led to mortals trying to explain more prima materia-related things, including their own anatomy and the nature of magic. In doing so, however, clear explanations couldn't be found, or when they were they didn't cover everything that prima materia did.
As a result, many things on Siderea began to fall apart. People struggled to use magic because they no longer believed it could work by simply thinking about it. Zodiacs like the Sagittarians stopped being able to hang between quadrupedal and bipedal form because the mechanics weren't fully understood, people failed to Disappear and instead simply grew lost or plummeted to their demises, etc.
Some people even began dying off because they thought too hard about how their very own bodies could possibly work, leading to localized outbreaks of people simply dying from the panicked realization that their world made little sense or becoming corrupted from their terrified pleas to be spared from demise.
As chaos reigned, people began noticing that the especially faithful, the unconvinced, and the ignorant seemed to be doing perfectly fine, leading to a resurgence of people actively worshiping the gods in hopes that they might restore the world.
The increase in prayers specifically involving being trusted to have the power to fix things in fact gave the gods the power to fix things to an extent, and so began the gods' campaign of making big public shows of "returning" people's magic.
As things began to settle down, the gods knew it would be too dangerous to let any knowledge of this particular apocalypse remain, lest people wonder why it happened and repeat history. They began a campaign of censorship and misinformation, inserting into history various conflicting reports and in general making information about the time period scarce. From a modern perspective it's usually seen as part of the Rigel era: issues with magic and the like transpired as a result of the level of corruption on the planet. In the rare event that it's not associated with corruption, the explanation was that it transpired as a result of a lack of faith in the gods - sometimes as a direct punishment from the gods or sometimes because the gods must need faith to be able to maintain the planet and the betrayal of them led to them growing weaker.
In order to protect things in the immediate era, however, the gods likely would have had to engage in some wide-scale memory-manipulation, though the exacts are a mystery that likely only they know...
Asterismorum was invented by the gods and their associates - particularly Raziel as well as Metatron, who wasn't yet even an archangel - to create a sort of "logic" to magic that would keep mortals occupied enough to not dig deeper. It was spread around as a way to help magic achieve consistent results, teach it to children and those who struggled with magic, and a way to enhance once's magical strength. As it caught on, the gods increasingly manipulated records in order to make it seem to progressive generations that it was always a thing and a fundamental part of magic, with those who use magic without it simply being of incredible power and mastery.

The Death of the Sky

Indirectly encouraged not to be so reliant on magic, mortals became increasingly interested in non-magic-based technologies.
At first this was fine, but as time went on society became increasingly built around non-sustainable resources. In particular the equivalent of fossil fuels were popular, but given that Siderea's core is full of prima materia this was reflected in its geologic resources... well it made coal and oil a hell of a lot more effective and efficient, but also made its byproducts even more dangerous and unhealthy than on Earth.
This was exemplified by the fact that all of the damage to the population, planet, and population beforehand had made Siderea's society considerably more stratified, mostly ruled by monarchies and other small groups that had gained reputations by staying in power during the End of Magic. Though many mortals had concerns and wanted to shift to more sustainable and healthy resources like wind and solar power and bring back magic into the equation, those in power wanted to stay in power (lots of competition goin on in this era, Siderea was very much not united anymore) through wealth and innovation.
Pollution became a significant problem, but it was insisted that the Virgos and Aquarians and the gods would simply take care of it all, as was their jobs, and so things carried on as usual.
Eventually things began reaching a breaking point, as Virgos and Aquarians began falling ill en masse, no longer capable of taking in any more pollution. Worse, many of them suffered from corruption due to the prima materia inherent in the pollution, some even becoming monsters.
Even Aquari - who was present throughout the atmosphere - and Virginis - who interfaced with Siderea's biosphere with Yggdrasil - grew ill and corrupted. While Aquari pulled back a bit and expressed open displeasure to the gods - who insisted mortals needed to make and live with their own mistakes - Virginis only worked himself harder.
Virginis inevitably reached the point where even he could carry on no longer, having taken on so much pollution that Yggdrasil began to rapidly wither, decay, and become consumed with corrupted rot. He collapsed, forcing the gods to take him to Serpentarius for treatment.
Aquari, reaching their breaking point, loudly announces that they're quitting their job of maintaining the atmosphere and encourages the other Aquarians controlling the weather throughout the world to drop their burden and save themselves, citing themself and Virginis as examples of how mortals have become so greedy that they've rendered even the gods incapable of performing their duties.
Most Aquarians do exactly that, plunging the planet into chaos as the atmosphere abruptly shifts from being actively manipulated by a bunch of air elementals to not being manipulated by anything at all, causing unpredictable weather throughout the planet. Virgos also cease their jobs of helping protect and maintain the biosphere, causing mass famine as the combination leads to many crops no longer being compatible with the land they're planted on.
Many of the disgruntled Aquarians and Virgos and their allies unite and found the nation of [ummm insert place here], a fiercely-guarded settlement where they could live in peace.
After telling off the other gods and defending their choice, Aquari elects to hide out with Scorpius, partially for treatment but mostly for the comparative lack of judgement.
Many who detested the reign of industrialists take advantage of the chaos to dismantle factories, power plants, and other such facilities, causing even more chaos in the process. Some chose to do so through incredible violence and destruction: the Aquarius Fomalhaut literally rained hell across the land, causing so much devastation that eventually the gods were forced to stop them.
As the atmosphere began to settle and pollution slowed, devastation continued as the natural weather patterns proved themself to be completely unlike the weather patterns the Aquarians had created and maintained for so long. Deserts were inundated with rain, forests died off, jungles were consumed by blizzards, bodies of water dried up, and populated areas suddenly had to contend with all of the severe weather Aquarians had deflected from them for so long.
While some Virgos and Aquarians did their best to mitigate some of the disasters and continue cleaning up corruption, it often came at a cost. Saints Astraea and Cendrillon became the final saints to die (aside from Ishtar and Mulapin, who live to this day) due to the former having taken on too much corruption and the latter succumbing to despair in response.
Eventually society began to adjust to the new world, but the damage was thoroughly done. A significant chunk of Siderea's population had been killed throughout the initial stages of the disaster and more still from the more subtle socioeconomic disasters that ensued. A considerable amount of infrastructure was devastated by the violence from both Sidereans and nature, leading to a tremendous amount of information loss.
The gods meet and accept their part in the disaster, deciding they need to become more aware of the burdens their fellow gods carry and the relationship the common mortal has with the world. They initiate the Incarnation Program, TL;DR forcing a part of their souls into the reincarnation cycle to experience mortal life, including that of other zodiacs. The first two cycles are designed to ensure they each experience life as Virgos and Aquarians to understand the burdens they're expected to bear.
Over time the wounds of the past heal and Virgos and Aquarians begin to manipulate the biosphere and atmosphere for the benefit of humanity again. Aquari agrees to return to overseeing the atmosphere again, but Virginis declines to remake Yggdrasil and, thoroughly heartbroken, never interfaces with the planet the way he did before again.

The Facet Conspiracy

During the Death of the Sky's immediate aftermath, a group of disgruntled Sidereans called the Facets found one another and began plotting to take the gods' power unto themselves, seeing them as ineffective. Aware of how prior efforts at overthrowing the gods had gone, however, the aim was to become "facets" of the gods, taking on the powers and duties they seemed to be ignoring or at least forcing their hands by stealing their power.
The Facets collect gemstones and other items associated with the gods, modifying their bodies to become perfect vessels for the gods' energy.
After years of research and preparation, gathering followers to help them who believed in their cause, the Facets engaged in a grand ceremony to channel the gods' energy and trap it within their bodies to use it as they pleased.
It worked!!
It worked too well!! They exploded. Rip.
This, however, brought the Facets to the gods' attention. They took pity on them and saw where they were coming from, especially considering the world was still a disaster and all of the gods felt bad about it.
The gods scraped up the Facets' souls and Saint Karkinos - who had died long ago and worked on the infrastructure of the moon - helped develop new bodies for them that could handle the gods' energy. That's all stuff for the Facets page but TL;DR the Facets kinda got their wish and became a secondary group of aides below the archangels. Though closely monitored and caged to some degree, the Facets were permitted to access some of the gods' power in order to effect change on Siderea.
As time went on the Facets proved themselves to be valuable assets, and the animosity and distrust between they and the gods wore down. Eventually the gods bestowed their Blessings on them and Arietis forged the Lustrous Regalia for them, and in modern times the gods easily trust them as much as much as they trust the archangels.
Actual timeline-wise, though, seeing things go horribly wrong successfully scared off their followers.
However, some of the Facets went right back to their followers to be like "hey!! we lived!! and won kinda!!", causing cults to spring up around them as they announced their affiliation with the gods.
Due to the sheer chaos going on throughout the world at the time, however, this wound up causing fewer issues than you'd think. The Facets took matters into their own hands, often learning that things weren't as simple as they thought but finding success in other areas. They mostly just helped the recovery process, and subsequent historical records wound up painting them as either a bunch of weirdos that put in admittedly admirable work or - more commonly - as religious devotees and humanitarians whose claims of having the power of the gods were interpreted as either strong faith or at times a sign that they must have received Blessings.
Eventually they too wound up pulling back as the burdens of being perceived as a god or otherwise godlike being became increasingly clear and they came to understand why the gods and archangels preferred less personal approaches. They began being formally trained by the gods and archangels and delegated various roles, eventually settling into very archangel-esque roles.

Age of Peace

The age where I don't have anything in particular planned LMAO so I guess it was fairly eventful overall. Lots of incarnations to learn from, the Facets grew more trustworthy, the gods settled back into more of a backseat at first glance but became more involved with manipulating society for the better in the background, etc. While they certainly had roots earlier, Nepsis, the Mayblossom Society, and other such organizations became more formally-defined.

the Uhhhh sandalphon incident

i need a fancy name for this.
Anyway a cult that needs a name wanted to gain control over the Dream Sea, and somehow they wound up with the idea that they could use a sacrifice to connect all of the Dream Sea to a single soul which they could then manipulate.
The soul they wound up picking was Sandalphon; still working on the specifics and I'd rather save it for Sandalphon's eventual page but in the gap between Metatron's first Disappearance with them as a tag-along and their reappearance their wakeself may or may not have been reduced to piscite by unsavory characters. Their dreamself, meanwhile, may or may not have been discovered by the cultists and manipulated by them because the fact that they had entered Metatron's subconscious in the first place TL;DR was kind of illegal.
One way or another the cult wound up using either Sandalphon's wakeself (if you can call it that anymore...) or dreamself or possibly even both as a conduit for their evil plans, which went... kind of right but also kind of wrong?
Sandalphon wound up becoming the Dream Sea itself, which needless to say was an overwhelming and terrifying experience even they could barely comprehend, especially seeing that they were entirely unwilling and not sure what was going on.
This caused chaos throughout the Dream Sea as every part of them cried out for help, leading to currents fluctuating, thresholds closing, and an immense outbreak of nightmares spawned from their distress.
No one was entirely sure what the hell was going on, and the unprecedented nature of the incident made Piscium unclear on what the specific problem even was, much less how to resolve it.
Eventually, though, Piscium figured things out and managed to calm Sandalphon down. They helped them figure out how to focus their consciousness and sensory experience, ending the disaster.
Piscium subsequently helped Sandalphon figure out how to shift their consciousness into a physical form, but had no idea how one might go about removing the Dream Sea's consciousness without harming either. At a loss, they proposed that Sandalphon - who they'd learned of long ago through association with Metatron and trusted well enough - be given the privileges of an archangel and that they use this to Siderea's advantage.
The gods accepted Piscium's proposal and Sandalphon agreed to try learning how to take advantage of their new reality, and to this day they spend most of their time overseeing the Dream Sea and redirecting things as needed much like how Aquari resides throughout the atmosphere.
Though quite a lot of text, this incident lasted maybe a week max. It's mostly notable for its lasting consequences and Piscium's openness about what happened, integrating Sandalphon's new form directly into the Dream Sea's... idk what word I'm looking for. You find info about them in your fish employee handbook now basically

Age of Mortals

The past thousand years or so, where the Vast Glow's sudden absence has left Siderea entirely without its Creators and the gods have ensured Siderea is a world ruled by its people. The general lack of the gods' (apparent) presence in every day life has led to the mortals becoming independent and confident enough to survive the trials that would soon await, though in the background the gods have carefully nudged things in the right direction.

Rise of Arachne

After many, many years of rumored sightings and urban legends, Arachne - a god created by the collective mortal pride in controlling Siderea's fate with their own hands - formally crawls out of the core, publicly and cryptically waxing about weaving the web and the death of the gods.
No one knows wtf she's talking about and Arachne's way of speaking - symbolic of the diverse experience of mortals and their desire to interpret the world around them for themselves - prompts everyone to, well, diversely interpret her words. She makes it very clear that she's some kind of new or lost god, too, making it seem like mortals really need to heed what she's saying.
Many interpret her words as a sign that the gods have died - explaining why they don't seem very present - or a prophecy that they Will die, beginning to panic about a current or pending apocalypse. Others instead interpret it as a call to action - that the gods must be killed for some reason or another.
Chaos breaks out as a result, with many unsavory characters showing their true colors under the belief that the coming end means they have nothing to lose. Cults interpret Arachne's words in a way that fits their belief, attracting new people and at times oddly bringing peace and cohesion to other places. Some, meanwhile, go around trying to find the pieces of Galaxias or engaging in sacrifice and unethical experiments to try and summon forth the gods to either kill them or to beg to be saved from a threat no one knows.
The gods have no idea who the hell Arachne is, but struggle to get any form of audience with her as her god powers make it easy for her to avoid them.
Eventually they manage to capture her, but they have no idea what she's talking about when they ask for an explanation of who she is and... how. They debate what to do with and about her, and in the heat of it they realize Scorpius has freed her and left.
The gods find Scorpius and Arachne together, and he explains that whoever she is, she isn't a threat. He explains that her words seem straightforward enough to him, and that rather than announcing any sort of call to action she was instead applauding mortals for writing their own fates and being independent of the gods, and that she was a symbol of their hard work who would be the hand that made all of their hopes and dreams become a reality. Arachne seems to confirm this, and also adds that she wasn't trying to flee from the gods but rather was simply very busy and also rather shy and a bit nervous about meeting her fellow gods.
The gods sort of accept this and then debate about what to do, but Arachne scurries off and makes a public apology to Siderea that she never meant to make so much chaos and that she has much to learn. In her own special way, of course. Subsequently she crawls back into the hole in the earth from whence she came, and everyone gets the impression that they fucked up. The gods may or may not have personally issued some sort of statement - probably Serpentarius at least - but at minimum they had their various plants kinda get things under control.
Once things began to settle, mortals were generally unhappy about how things had played out, how easily they turned on one another due to one figure being interpreted so wildly differently. The Siderean Council was founded as a result: a world government body consisting of a variety of zodiacs from across the world of various walks of life, selected through a mix of meritocracy and democracy. They would meet regularly to discuss issues from across the world including struggles of specific zodiacs, publicly broadcasting meetings and encouraging others to send in their own concerns to be addressed. Whatever the Council decided upon is what the world decided upon, and if they could not come to a conclusion on some matter they would have to continue meeting and discussing until they could, lest whatever issue plaguing the populace be put on hold.

The Return of Arachne

A couple hundred years later or so, Arachne sightings became more common again. Furthermore, there were rumors about there being more than one Arachne...
The gods investigated and found Arachne hiding out in the Godless Lands, who felt ready to try and re-enter Siderea again but would try to be more subtle this time. She hoped to do this by... making her own zodiac! The Araneans!! Check 'em out guys!!
The Araneans were created by converting existing people into spider-people, mostly cultists but every once in a while a stray traveler - like Ariadne - whose life she'd saved by using the conversion method. This kinda made the gods' eyes pop because a new zodiac was unprecedented, but then so was the idea of a new god, so... as long as it was all consensual, maybe this is what the collective heart of mortals truly desired...?
The Araneans began slowly leaking into society, generally in traveling groups with some explanation of who they were. At first they just hung around in the dark corners of society and odd places like Dschubba where people just assumed it was some weird body mod trend, but the gods grew nervous about some of the more panicked receptions and wanted there to be some sort of formal announcement of they and Arachne's existence.
Ariadne, who Arachne claimed to be her saint at some point or another, agreed to be the head of the operation and the gods arranged for her to meet with the Siderean Council. There she announced the existence to the Araneans to them and explained some things, assuring Siderea that they meant no harm and had various reasons for wanting to become Araneans.
Reception was... mixed, but the fact that the Siderean Council publicly accepted that they existed and wished to help integrate they and their patron god into society ensured that society didn't immediately freaking out again.
Still, not everything went smoothly. An outspoken priestess of Arachne, Haniel, was killed when trying to reach out to those who treated her and her kind like a monster and harbinger of doom. This incident became an intensely hot topic, and the Siderean Council formally condemned the act, putting into motion a formal decree of acknowledgment of Araneans as an official new zodiac. Haniel, meanwhile, at least wound up becoming an archangel, further cementing to the gods that Arachne and her kind were here to stay and it was time they made room for her in the Cosmos.
Though it took some time to get things organized and to get to know the Aranean populace, the Siderean Council eventually wound up adding Aranean chairs to the council, officially cementing them as a zodiac.
At some point after this but before the next era, Metatron finally ends up getting sacrificed by randos and becomes the final archangel. Yeah, that's right. Fuckin' Arachne got an archangel before poor Virginis did. That's okay though bc Ariel basically is Virginis' archangel anyway and also Raziel, really...
Arachne also wound up somehow wholesale creating her own personal Facet, Hecate, at some point in hopes of further fitting in with the other gods.
Though Araneans became accepted, they and Arachne still remain very reclusive and they are seldom seen outside of a small area, their usual more accepting haunts, and the Siderean Council, still fearful of backlash. For better or worse, though, the spotlight would soon be taken off of them thanks to...

The Great Cetan Invasion

The Cetans started coming back from the Great Cetan Exodus!! Yaaaaay!!
Oh uh-oh they were corrupted by space and grief. Bad!!
Monster whales started crashing into the planet, destroying quite a lot in the process.
Sidereans came together to defeat the monsters and create warning systems when an impact was suspected, and various gods (particularly Cancri) were briefly sighted for the first time in ages defending the planet.
As information spread and became more clear, however, people realized what was really happening; that the monsters weren't alien invaders of some sort but rather were corrupted Cetans that they were killing.
Some insisted that killing them was all they could do, but most wished to figure out how to cure them and figure how why they had return and what ill fate had befallen them. The Siderean Council met over this and ruled that they couldn't possibly carry on the way they were knowing that the "monsters" were their very own fellow citizens, however detached from modern times they might be. They announced that Siderea must shift focus onto containing any corrupted Cetans, with killing them only being an absolute last resort if containment was proving to be absolutely impossible.
Though this proved to be far more difficult than just killing them, the Sidereans did their best and successfully contained just about every Cetan that broke through the gods' initial attempts at intercepting them.
As the Cetans were cured, they revealed that Cetia had declared that she would carry on the search for the Fallen Star and Risen Star alone. She could tell that the other Cetans were growing increasingly weary and homesick from their travels, and many of them had since changed their mind and no longer believed the High Star's components should be found but felt they had come too far to turn around. She used Eris to open up portals to lead them to Siderea's vicinity, cautioning them not to wander. The distance was so vast and the path home so uncertain that she needed to open up more of a tunnel than a portal, so it was critical that they follow the path straight ahead and not attempt to turn back.
Wander some did, though. Through varying mixtures of curiosity, boredom, impatience, worry, and regret, many Cetans strayed from the path or otherwise brushed too close to the edges. Combined with the degradation the monotony of their ages of travel had caused to their minds and the various damages their space journey had inflicted onto their bodies and souls, it wasn't hard for these Cetans to end up becoming corrupted. Those who wandered outside of Eris' path still wound up in the same place - drawn by the heart to the place they so desired to turn to - but dramatically warped and at wildly differing times.
In truth, though, the amount of corrupted Cetans were in the minority; most obeyed Cetia and continued straight on ahead, returning to Siderea more subtly by delving into the abyss back home and not crash-landing in the middle of major cities. The "invasion" had begun before most could realize they were gradually returning home, naturally distracting most of Siderea and making subsequent "normal" returns go unnoticed entirely. The fact that this immense invasion was a small fraction of the returning Cetans, though, went to show the sheer number of Cetans who had left alongside so long ago.
When the "normal" Cetans who traveled a bit slower realized what was happening, most of them remained in space to help the gods in trying to intercept and cure their peers, once more going to show the sheer amount of fuckin space whales we're dealing with here when you had most of them catching each other and yet Siderea was still dealing with a whale apocalypse. They sent out prayers to Cetia, asking for her help.
Cetia responded practically immediately; upon hearing news of what was transpiring, she came to the crushing realization that she truly was betraying everything her beloved High Star ever wanted. Not only did she know deep down that they didn't wish to be found, but she had completely abandoned the planet and the people that they had entrusted to her. Devastated but desperate to make things right, Cetia rushed home and immediately took very personal charge of ending the invasion... something that was quite shocking to the mortal populace, considering how infrequently the gods ever made physical appearances.
While they let her do what she needed to do first, the gods subsequently urged her to come back to the Cosmos to explain many, many things to her and also cry a lot bc they all missed each other ;___;
I can't find a less awkward place to stick this but Arachne was a big help throughout the invasion, with the Araneans often crawling out of the woodwork to help catch and contain fallen Cetans. This helped boost public opinion of them.
The invasion came to a swift close, with a task force of Cetans working alongside Cetia and Cancri to this day to efficiently intercept any other Cetans who return, though it seems everyone's been accounted for now. Still, it's helpful when it comes to dealing with, well...

Age of Unity

The thing about a bunch of corrupted whale portals opening up is that it tends to puncture the veil of secrecy you didn't really even know was surrounding your planet.

The Offworld Era

The gods were so occupied with trying to fix Siderea itself back up after the Great Cetan Invasion that they didn't realize Siderea had suddenly become visible to the rest of Entirety.
Reality-travelers and unfortunate random souls stumbling through random portals (an RPverse staple!) began finding themselves on Siderea, much to the confusion of the populace.
As these incidents became more common - especially as the willing arrivals went back home and told more people about Siderea - the gods and mortals alike realized what must have happened and what the consequences now were.
The gods debated trying to contact the Creators to see if they could put the metaphorical wall back up, but the existence of offworlders had become so widely known and so openly addressed by the Siderean Council that they held back.
The Siderean Council announced that they had accepted the Araneans, they had done their best to welcome the Cetans back home, and overall so much of their efforts had been about uniting Siderea and seeing the value in everything everyone has to offer. If that was the case, then, so long as offworlders continued to come in peace, why not embrace them? If offworlders now had access to Siderea, then perhaps it was a sign that Siderea was finally strong enough to stand on its own and brave any threat the universe might have for them. It was time to share all of the wonderful things about their planet and learn about all of the incredible things out there that they'd been missing out on since Siderea's creation.
With that, Siderea got to work laying out rules and regulations regarding offworlders, with the gods assisting by creating systems to detect portals and offworlders and ensure they wound up in specific locations so that mortals might keep track of them. Astra - the world capital - became the hub of all things offworld.
After a few decades of increasing offworld interest and things going pretty smoothly, the Siderean Council began organizing the Siderean Offworld Festival: a festival in Astra dedicated to showing off Siderean culture and inviting offworlders to show off their own as well.

Modern Day

That's now baby!!!!!!!!!!!!!!!!!!!!!!
In modern times things are about as peaceful as they can be. Thanks to being viewed by other worlds as a planet rather than a bunch of continents and countries - something the Siderean Council has more or less encouraged - Siderea has only become more united over the years. It's still a diverse people with plenty of its own issues, but the days of widespread war and conflict are a distant memory now.
Because of this unity combined with their actions during the Great Cetan Invasion, the Araneans have become more widely accepted, especially since offworlders generally have no idea that they weren't just a basic zodiac there from the start. They still remain fairly reclusive, though, but this seems to change more and more quickly over time.
In terms of dealing with offworlders, Siderea hasn't had any major incidents. It's still about as backwater as a planet can get, so it's difficult for anyone incapable of reality-hopping to get to unless they "luck" into some random isekai portal. The gods and their aides, feeling like Siderea's populace is now well and truly in good hands given how the last few major world incidents were handled, have now shifted focus to monitoring the flow of offworlders and their actions, unhesitating when it comes to banishing anyone who seems like they're going to be a problem.
Still, they're starting to realize just how valuable Siderea as a planet is and how unique their resources are, prompting them to always act with extreme caution. The gods haven't quite realized that they're possibly the most powerful beings in Entirety at this point, though, so they likely don't need to worry too much... but at this point they've been through so much that they figure it's better to worry than to regret trusting in their own power. That sort of thing tends not to end too well, they've found.
I guess I should mention uhhhh New Aethiopia gets founded a few decades prior to current time, if even that long??
Really I could mention a lot of small things like people being born and some people's backstory deets but I think I'll not, at least for now.

Timeline