Wars of Reaving
The Wars of Reaving were an exceptionally violent series of conflicts in BattleTech that happened out in Clan space. These wars were so destructive and so deleterious to the Clan cause that it crippled any possibility of future Clans returning as a major force in the Inner Sphere for good, and utterly broke their society.
Prelude to War
The Clan Invasion had happened, and while it started strong and several clans had made meaningful gains, it ultimately had failed miserably, and the subsequent War of Refusal, which ended even more poorly for the Clans, had their entire societal mindset fractured. They had long believed they would return to the Inner Sphere as conquering heroes or enlightened warrior-kings, and had that particular belief both shattered and warped by interaction with the Spheroids, who only ever saw them as one thing: Invaders. Their previous Crusader/Warden political factions had mutated into Crusaders and Wardens, but also Invader and Home Clans; Clans separated by whether or not they had a foothold in the Inner Sphere or not, and whether or not they wanted to continue that.
And then Smoke Jaguar wasn't just defeated in the Wars of Refusal, but outright annihilated. And Clans Ghost Bear and Nova Cat said "lmao bye nerds" and went to go to their ultimate fates in the Inner Sphere. This meant that massive swathes of the otherwise tightly compacted Clan Homeworlds were officially up for grabs, and the subsequent Wars of Possession created more rifts among the Clans than there had ever been before. In all this chaos, Clan Steel Viper returned from the Inner Sphere, broken and furious that they'd been so utterly outclassed by fucking Spheroids, and set about to building up their resources among the Homeworlds to work off some steam and build for the future, while allying themselves with Clan Cloud Cobra and Star Adder, creating a Snake Alliance. The consequences of this action would have disastrous effects on the Clan homeworlds, though nobody knew it at the time.
The Rise of the Bloody IlKhan
In 3067, the Clans began what they thought was going to be a normal IlKhan selection process, and placed Fire Mandrill's Khan, Garrett Sainze in charge. The reasoning was that while Sainze was honestly kind of an over-aggressive idiot, Clan Diamond Shark saw the writing on the wall as many of the major powers were suddenly being superceded on the Grand Council by the Snake Alliance's growing influence, and wanted to personally check them. Sainze was unfortunately just as much of a hothead in charge of the entire Clan society as he was when running Fire Mandrill, and touched the raw nerve that the Great Refusal had become; sparking a massive fight in the grand chambers, and ultimately his death by Trial of Refusal thanks to Clan Golaith Scorpion's Khan.
Because Sainze was dead, the election had to take place again...and this time Steel Viper's Khan; Brett Andrews, would succeed him. The Council believed that he was going to just re-start things and move on as intended, but Andrews didn't have any plans for that.
Andrews, a veteran of the Invasion and also the subsequent Wars of Refusal, believed that a contamination, a "taint" had befallen the Clans from contact with the Inner Sphere; as they had picked up such dishonorable tactics as bombardment and artillery strikes, and had brought them back to their homeworlds. To him, the Spheroids had begun to rot the clanner way of doing things from the inside out, and if they were ever going to invade the Inner Sphere again, they needed to purge these elements from their ranks entirely, and that meant the current Spheroid Clans, as well as any who dared question these orders; as the Diamond Shark Khan found out all too quickly in the middle of that room. He even made his point clear by completely disabling the comms grids that connected Clanspace and the Inner Sphere.
From there, the Wars of Reaving truly began.
The Abjurring of the Spheroids
Understandably, this didn't sit well with a number of Clans due to their overall philosophies already not entirely being laser-focused on winning the Clan Invasion years after it had ended, and in 3069, Clan Diamond Shark thought now was a good time to fuck off entirely to the Inner Sphere and did so; making whatever deals they needed to in order to get out before the fighting got bad. Clan Snow Raven, in similar straits and definitely not interested in dealing with whatever the hell Steel Viper thought of their already Spheroid-like nobility structure, and fucked off to join the Outworlds Alliance; ensuring that even if they were tasked with rebuilding a Periphery state, they still had the cash and resources to survive any oncoming problems, which ultimately never came. Hell's Horses and Ice Hellion also fucked off trying to build their own fortunes in the Inner Sphere, and the rest waited with guns at the ready for what came next.
The first shot across the bow came in April, as Andrews officially abjured Clan Wolf from the Clan Homeworlds. The Wolf Khan audibly laughed him off, stating he could go fuck himself in front of the entire Clan Council. Andrews demanded Annihilation, but the Council, both egged on by the few Invaders left and Clan Coyote, simply got it down to Abjuration. Andrews still insisted on fighting the Wolf, and began blowing up their Blood Chapels. Clan Wolf wouldn't take it lying down, and then took Kerensky Blood Chapel and challenged the entire Home Clan infrastructure; if they wanted to be Kerensky's children, they'd have to fight for it. Of course, Clan Wolf had squirrelled away the genetic material for the Kerensky bloodname off-planet, and by the time the battle ended, Clan Wolf emphasized their Khan's "Go fuck yourself" by blowing up the chapel anyway, stating that Kerensky's legacy didn't deserve such ungrateful brats attempting to lead it.
Next, Andrews demanded the abjuration of a bloodname from Jade Falcon, who of course did not take kindly to that particular request and killed a high ranking warrior of Steel Viper. Incensed, he blasted their blood chapels into dust and abjured Jade Falcon.
Clan Coyote realizes they live in A Society
Clan Coyote, pissed about all this, had suddenly been contacted by a secretive group of Scientist Caste members known as The Society; a secret organization that plotted the overthrow of the Warrior Caste in order to allow the Scientists to rule supreme. Coyote, already a science-focused Clan that'd had a hand in tons of Clanner technology achievements that they'd received ultimately little recognition for, decided that they would throw their lot in with them and helped the Scientists begin their revolt. It was a spirited fight, but ultimately ended in a complete failure and a panic purging of almost every clan's Scientist pool with some exceptions. But the blame for this event, rather than on an ultimately unsustainable social structure; fell on Clan Coyote since their gear still had all their logos on it. Andrews demanded annihilation once again, but Coyote's warriors protested that many of them hadn't been involved in this at all. To prove it, he declared a Trial of Cleansing; they would personally slaughter their entire Scientist Caste, and any warrior who sided with the Society was to be purged. Though Clan Coyote survived, they had lost their entire research and development capabilities, and half their forces, as well as being otherwise shunned by the other Clans thanks to their actions; only Clan Cloud Cobra would seek them out later in order to further their strength.
Beheading the Snake
After all of this death, bloodshed, and kicking out of any undesireables, Steel Viper was feeling good about themselves...right up until the next grand council. The orders of business were as per usual; certain bloodnames were to get reaved, Clan Goliath Scorpion got the boot, and everything was going fine...until Star Adder's Khan took the stage, and announced the next clan to be reaved was in fact Steel Viper itself. For all of Steel Viper's claims of purity, they themselves had ultimately undergone many political games in just such the way that the Spheroids would in order for Brett Andrews to keep power, and had crippled the Clans in many of the ways that mattered. Andrews in a fit of rage chose to invoke the trial of refusal, and then just shot the Star Adder Khan, in clear violation of the rules of the Grand Council, sealing their fate. As he was placed in custody, he demanded another trial, and Star Adder's SaKhan, who was buddies with the man who was just shot in cold blood, promptly beat Andrews to death with the enameled ceremonial mask of Star Adder. Steel Viper itself would quickly find it's actual grip on the situation was tenuous at best, as every clan left in Clan Space kind of hated having to check themselves for "purity" or whatever the fuck Andrews meant by that, and pretty quickly tore through them like paper. Star Adder would take in any of the survivors, and the Wars of Reaving were at last over.
Aftermatch
The Wars of Reaving completely fucked up the Clanner way of life.
Initially, it looked like Clan Goliath Scorpion had ended up becoming the real winner of the conflict thanks to having not been involved in the invasion and having been large enough on it's own, but was quickly booted out of the Homeworlds thanks to genetic tampering being discovered, and it ultimately left Clan Star Adder as the top dog in Clan Space for the time being; having abjurred, annihilated, or absorbed most of it's competition, and having allied with Cloud Cobra and the newly created Stone Lion. It did however ultimately ensure that the Clan Homeworlds were completely and utterly cut off from anything going on in the Inner Sphere or even Periphery out of a fear of "Spheroid" influence, and that they would alone Shepard humanity through the Kerensky Cluster, and the Kerensky Cluster alone.
In the deepest irony, the Spheroid Clans somehow came out the victors in all of this, since they actually got what they wanted; less homeworld interference in their quests to conquer Terra. Clan Wolf, even though it'd down the middle thanks to it's place as both Abjured Home Clan and Invader Clan, eventually ended up being the IlClan out of all of this.
The Clans who didn't make it
- Ice Hellions - a bunch of blitzkreig obsessed dimwits who fucked off from Hell's Horses when they said they'd come together to face their foes and carve out their own space, they basically got caught in the same web of bullshit the Steel Vipers had in civilian revolts, and attempted to fight the now very real and very dangerous Rasalhague Dominion. They got absorbed by Clan Scorpion after they contacted them and just told them "hey, it's easier if you just come in and enjoy some peyote with us rather than get blasted", and they did.
- Hell's Horses - Only on this list on a technicality. Hell's Horses split in half thanks to yet more Reaving, and the half that stayed in the Clan Homeworlds became Clan Stone Lion.
- Fire Mandrill - Already a fractious Clan within a Clan with a lot of internal strife, Fire Mandrill's Khan getting murk'd and then being used as an example of Clan "taint" caused the already weakened Clan further issues. Their Kindraa tried to band together to stay alive, but were ultimately demolished.
- Burrock - Had already been absorbed at an earlier period of time, was briefly revived thanks to Clan Star Adder being stupid enough to give enough of their warriors over, and promptly had to put their creation down.
- Steel Viper - Started all this shit, and then promptly got shredded for it.
- Blood Spirit - An agitator in favor of the decision-making that Steel Viper had been rolling with, eventually got pounded into dust after Steel Viper's annihilation.