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"Hear the cannons roar! Revel the noises of unmaking, in the Thunder that heralds doom!"
Sorakae Vhak, beginning the Siege of Telos V

The Brethren of Thunder are a small warband of Iron Warriors of some infamy, composed of the remnants of the ancient Lyssatra warrior-society, sundered from the remnants of the Grand Battalion that turned on them for their cult-like ways. Now they fight for none save themselves, a wandering host of unhinged Chaos Space Marines obsessed with both creation and destruction, fighting for the sake of these two concepts alone.


The Burned Men

Seldom known to those that were not amongst the ranks of the 4th Legion during the halcyon days of the Great Crusade and the tumultuous wars of the Horus Heresy, within the ranks of the Iron Warriors existed a series of long-standing warrior societies, situated just outside of the Legion's military hierarchy and order of command. They were the Dodekatheon, the Apolakron, the Kheledakos, and the Tyranthikos, each so firmly entrenched within the culture of the sons of Perturabo that they resisted even the corrosive influence of Horus' Warrior Lodges, and yet none were more obscure yet infamous than the Lyssatra, the Brethren of Thunder.

Disparagingly known amongst their battle-brothers as the "Burned Men", the Lyssatra were a society composed of the Iron Warrior's most unhinged and war-scarred, so obsessed with creation as a means of destruction that they were almost like a cult rather than a gathering of like-minded Space Marines. They were weaponcrafters of the highest order, delving into the more arcane arts of technology beyond the extent of what many would consider sane or practical, and as a result they were a pariah group within their own Legion, a small cell of outcasts that many amongst the 4th Legion preferred to keep out of sight and out of mind.

The depravity of the Lyssatra only grew with the onset of the Horus Heresy, exposing them to the mysterious arts of warp-craft. While the rest of the Iron Warriors were content to keep the powers of the Horus' newfound daemonic allies at arms length, many of the Burned Men eagerly embraced these newfound powers in order to find new ways of pursuing the creation of the perfect weapon. Chief amongst these individuals was Sorakae Vhak, a Techmarine and master artificer who had long since fallen in with the Lyssatra. With the discovery of the reality-altering properties of the Warp, Vhak began to research into the application of these properties to conventional weaponry, and soon embarked upon the creation of what the galaxy would later term "Daemon Engines". His constructs and designs were wondrous to his fellow Brethren of Thunder, but to the rest of the 4th Legion it only served as the earmarks of a moral threat in their midst. Tensions arose between Vhak's coven of followers, that would have no doubt led to an internal conflict, if Horus hadn't lost his war again the Imperium.

With the death of the Warmaster, the Iron Warriors retreated back to their homeworld in an attempt to hold on to the pocket empire they had created from the star-systems surrounding Olympia. Vhak and his disciples were amongst the sons of Perturabo that entrapped the Primarch Rogal and his Imperial Fists within the Eternal Fortress of Sebastus IV, and took great pleasure in gunning down the Imperial Fists within it's trap-laden confines. This massacre would earn their Purterabo his dark apotheosis in a Daemon Primarch, and with his accession the Iron Warriors left for the Eye of Terror, leaving Dorn to wallow in his abject failure.

A Battalion Divided

With the 4th Legion's settlement on the Daemon World of Medrengard, the Grand Battalions were divided up and sent forth to claim vengeance in the name of mighty Perturabo. Vhak, now a fully-fledged Warpsmith, was assigned to the 16th Grand Battalion under the command of Warsmith Hurosus, a staunch traditionalist of an Iron Warrior who longed to restore the Legion to it's former glory. Unsurprisingly, Hurosus and Vhak did not at all get along, the Warsmith considering Vhak to be a dangerous radical while the Warpsmith considered Hurosus to be a narrow-minded zealot. Yet despite their animosities, the two both had skills required to effectively maintain the 16th, and thus they tolerated each other for the time being.

Laying siege to the Imperial Fortress World of Galahad, the 16th Grand Battalion cracked open the once-impregnable bastions and stormed the planet's most durable holds, massacring it's defenders and enslaving it's civilian population. From their they proceeded to expand upon the already formidable structures, draining oceans and ripping down forests to make way for an ever-advancing network of fortresses and military installations. Soon the surface of Galahad was little more than an expanse of unforgiving walls, towers, and crenelations, it's once-pristine blue skies now shrouded by industrial smog. Vhak himself commissioned an entire section devoted to furthering the goals of the Lyssatra, complete with a cavernous weapon-hangar, an extensive armory, and a gargantuan war-forge of his own design. He would rarely emerge from that place, save to test one of his various "creations" during the 16th Battalion's many conquests.

From Galahad the Iron Warriors poured forth to savage the Imperium in the name of mighty Purterabo, but as their position grew all the stronger, tensions were beginning to spill over within the Battalion. Even after all these years Vhak still kept the traditions of the Burned Men alive, and that attracted followers, particularly those whom had never part of the 4th Legion in the days of the Great Crusade. The main core of veterans within the 16th Grand Battalion sided with Warsmith Hurosus, distrusting both Vhak and his attempts to re-establish his radical warrior-society, but their numbers dwindled with each passing day. The situation escalated as the Battalions stored gene-stock began to dwindle, forcing the Apothecaries to splice their genetics with all manner of progenoids taken from other Astartes, and giving rise to all manner of "Half-Breeds" within the ranks. These unfortunates were reviled by their more traditionalist kin, and thus they would flock to the Warpsmith, who cared little for their lineage so long as the Lyssatra's ways were kept alive through them. Hurosus feared that with his newfound influence it wouldn't be long before he tried to grasp for dominion over the 16th, and so he struck first.

Two entire squads of Terminator-Armored Dominators stormed Vhak's war-forge intent on putting down the Warpsmith, only to find the forge derelict, empty, and filled with hidden Melta Charges. The fiery explosion that claimed their lives was only the first of many, as with a single command Vhak initiated hidden protocols within every single Servitor he had constructed, the cyber-menials having been spread throughout the confines of Galahad in preparation. Harmless chemicals stored within their bodily compartments ran together, combining in volatile mixtures and detonating all across the planet's adimantium and rockcrete landscapes in massive alchemical conflagrations. Chaos ensued shortly afterwards, thousands of slaves and Iron Warriors alike having perished in one fell swoop. Vhak marshaled his chosen warriors, and Hurosus did the same. The War of Iron had begun.

Warsmith Versus Warpsmith


Warband Culture

The Brethren of Thunder were founded on the ideals and creeds that once founded the Lyssatra, and as a result those ideals have evolved into something akin to a cult. All of the Brethren, from the highest Warpsmith to the lowest Thorakite, are obsessed with creation and destruction as an end to itself, reveling in the paradoxical implications of such a belief. They strive to create, both in the literal and metaphorical sense, so that they might become the ultimate weapons, and destroy, so that they might bask in the glory of the devastation wrought by their hands. All is a means to this end, and to the Brethren, nothing else matters. Things are born, things die, and they simply delight in their ability to replicate this process.

Because of this belief the Brethren of Thunder are almost zealous when it comes to the acquisition of technology, the more advanced and arcane the better. In their endless quest to create the ultimate weapons of mass destruction, they augment their wargear and even themselves with ill-understood mechanisms plundered from xenos sepulchers and daemon-infested hellholes alike, heedless of the risk. Their Warpsmiths are endlessly inventive, constantly experimenting for the sake of experimentation and giving birth to all manner of diabolical masterpieces as a result. Because of this, one of the Brethren's main goals is the acquisition of new technology, and they have often persecuted entire campaigns for that goal alone.

Despite their cultural differences, the Brethren of Thunder still consider themselves to be Iron Warriors, and thus still withold many cultural aspects of their former Legion. For all their cult-like ways the Brethren to not worship Chaos, but like most sons of Perturabo they see it as a means to an end and little more, though their mannerisms have lead many to believe that they have been hopelessly corrupted by the Ruinous Powers, for few outside the Iron Warriors know of the Lyssatra and it's ancient origins.


Sorakae Vhak is the absolute commander of the Brethren, the Warpsmiths who study under him making up his elite inner circle of lieutenants and disciples. The remainder of the Iron Warriors are few in number, barely three companies worth, but their small size belies their effectiveness. Most if not all have served Vhak for millennia, and their exotic wargear and unearthly augmentations have only made them all the more formidable opponents, serving as battlefield commanders and shock troops. Their overall organization has varied little since their days within the Legion, still organized into Squads of roughly ten to twelve led by a Squad-Sergeant, the only difference being that their are no squad specializations, each Warrior carrying whatever weaponry he desires into battle.

Other than the Iron Warriors and Thorakite Cultists that serve under them, the Brethren of Thunder maintain a surprisingly large motorpool mostly made up of re-purposed Imperial vehicles, modified and refurbished to the point where their original models are practically unrecognizable, though they still retain a few Crusade-era relics. Most are siege engines, artillery canons, and the like, operated by the Thorakite and coordinated by the Iron Warriors for maximum efficiency and destructive effect. However, due to the extensive modifications wrought upon these machines, no two are exactly alike in terms of design and armament.

The Thoraktie

"We were told the enemy had cultists fighting under their banner. We were expecting a horde of raving fanatics, not... this."
—Major Alexius of the Cadian 337th Infantry, during his debriefing

Named after the Selucid Thorakite, the Olympian-born Imperial Army regiments that once accompanied the Iron Warriors in their conquests, the Thorakite are mortal cultists devoted to the creed of the Lyssatra. Originally they were little more than slave-militias that fought for Vhak during the War of Iron, but since his departure from Galahad they have quickly become one of the Brethren's most valuable resources. Without their sheer manpower the warband would have struggled, but with it, they thrive.

Unlike most cultists, the Thorakite are as cold and disciplined as their masters, sleep-taught essential training and armed with wargear that makes them almost the battlefield equivalent of Imperial Storm Troopers. Clad in khaki fatigues and flak armor the color of burnished iron, the Thorakite come into battle armed with the teeth with Lasguns, Autocarbines, and combat knives, marching into battle alongside the Iron Warriors who command them. Others serve as tank crews and artillery teams, operating the Brethren's vehicles at their behest. Many are further enhanced through bionic augmentation, a symbol of the Brethren's favor, some to the point where they resemble intelligent servitors.

The Thorakite are divided into groups of twenty known as Divisions, each one commanded by a high-ranking cultist known as a Marshal, and can serve as either an infantry group, a number of tank crews, or a number of gun crews. Oftentimes a Iron Warrior can and will assume command over a division of Thorakites, serving as it's leader until such a time as the Warrior no longer requires the cultists' services in battle.

The Iron Coven

Given the Brethren's obsession with technology, it is no surprise that after so many years exposed to the corrupting powers of Chaos, some of their number have contracted the insidious Obliterator Virus. This loose band of Obliterators and Mutilators is referred to as the Iron Coven, made up of those who have succumbed to the techno-virus and been transformed into insane hulks of fleshmetal and malice. They are imprisoned within the bowels of the Brethren's flagship, the Chariot of Lochos, until such a time when the warband has need of their brute strength in battle.

When released into a warzone, the Iron Coven attacks in groups, ripping through enemy lines in a disorganized mass as their flesh-weaponry spews death and shreds lesser opponents to gory ribbons. Their is almost a strange pack mentality to the Coven's assaults; individual Obliterators taking up positions as ranged support while their Mutilator brethren lead the charge, corralling groups of victims together so they might make their massacres all the more bloody, even seeking out enemy leaders for seemingly no other reason than to find more challenging sport. This behavior is erratic and random at best, but it certainly is effective at destroying opposing forces.

However despite their usefulness, the Brethren of Thunder only release the Iron Coven as a last-resort tactic, for the Obliterator-infected recognize no authority save their own, and would gladly butcher their fellow Iron Warriors given the chance. Because of this they are only given free reign when unstoppable force is desperately needed to further the Brethren's advances.

Favored Tactics

"Hear that? Isn't it beautiful?"
—Thorakite-Marshal Toven, listening to an Artillery Strike

True to their heritage, the Brethren of Thunder specialize in the construing and besieging of both defensive and offensive fortifications. Utilizing scores of siege tanks and artillery vehicles, the Brethren typically break open enemy defenses through sheer firepower, their Thoraktie cultists swarming in to serve as the main infantry offensive while the Iron Warriors themselves act as shock troops, striking at important strongpoints and defensive bastions. Under attack from multiple locations at once, usually the enemy crumbles under their relentless onslaught, though if their resistance persists for longer than anticipated the Brethren will oftentimes release the dreaded Iron Coven to finish off what stubborn remnants remain.

The Brethren have also shown to be quite adept at armored warfare, unleashing coordinated tank battalions to engage enemy armor and devastate enemy infantry. Their extensive range of armored vehicles allows for a large degree of tactical flexibility in these situations, especially when confronted with an enemy armed with anti-tank weaponry, for the sheer amount of myriad modifications wrought upon said vehicles makes them difficult to repulse through conventional means.

Exotic Weaponry

The Brethren of Thunder have crafted all manner of unorthodox and ill-understood weaponry, courtesy of the dark genius of their Warpsmiths. Many devices are only used once or twice before being discarded so that the Warpsmiths might continue on to the next project, but the most commonly encountered of these rare weapons are:

Cyberdaemonic Viruses

Crafted from the data-remnants of tormented Machine Spirits, Cyberdaemons are quite literally daemonic entities bound into a form of a coded sequence, transforming them into sentient viruses capable of infecting and and corrupting almost any form of machinery. When introduced to a technology, a Cyberdaemonic Virus attacks the object's Machine Spirit, annihilating it under an onslaught of nonsensical warp-algorithms before taking complete control. Once integrated the Cyberdaemon can exert it's full influence on whatever it is currently possessing, twisting and corrupting it into a shape more pleasing to it's whims. The end result of this transformation is a malformed technological abomination, slaved to the will of the Cyberdaemon possessing it.

Cyberdaemons, like Machine Spirits, grow more powerful the more they are used, and thus the youngest of their kind are only capable of infecting a single weapon or bionic implant, while the most venerable Cyberdaemons are capable of infecting entire spaceships. Oftentimes enemy vehicles will attack the Brethren only to be hit with an unknown salvo of firepower, then watch in horror their own war machine begins to rebel against them, wreaking havoc within enemy lines.

The only main drawbacks to Cyberdamonic Viruses is both their rarity and their offensive implications. They are notoriously difficult to create, impossible to mass-produce, and can only be introduced to an sort of technological system through direct contact with it's target, usually through data-packaging "Viral Bombs" and similar devices. However, giving a Cyberdaemon access to technology is allowing it to roam free, and once it has possessed a device it's behavior is complete unpredictable. Thus, the Brethren's forces usually clear the area before unleashing a Cyberdaemonic attack upon their foes.

Atomization Munitions

Taking the form of various heavy ammunition-types, such as tank shells and orbit-to-surface missiles, Atomization Munitions are the result of the Brethrens integration of unknown xeno-tech into their offensive weaponry. As the name implies, Atomization Munitions contain technologies that allow it to reduce it's target down to it's component atoms, making it excellent during a prolonged siege, disintegrating any enemy fortifications in a single shot.

Most of these Munitions consist of a durable adimantium shell casing, sturdy enough to resist even an orbital strike without fracturing so that it will not damage the delicate technologies within. Once launched, the shell deals a considerable amount of damage through sheer kinetic force of impact, at which point sensors within the casing activate it's inner mechanisms, which radiates high-speed photons that fracture any molecular bonds they come into contact with. As a result, anything within the vicinity of begins to atomize into a cloud of base protons and neutrons, the radius of the destruction depending on the size of the Munition.

While extremely effective at reducing virtually any sort of physical defense to nothingness, Atomization Munitions are used sparingly by the Brethren, for they are incapable of replicating the xeno-tech that allows these weapons their unique properties. Only when overwhelming force is required to they even consider to expend one of these valuable devices.

Psychic Dampeners

One of the main problems the Brethren have stumbled upon during their conquests is their vulnerability to those who possess psychic powers, as they themselves possess no psykers within their ranks. Thus the Psychic Dampeners were created as a means to level the playing field, by defending against the ethereal powers of the warp and then turning them against their practitioners. These devices consist of small boxy frames of blood-sanctified ceramite, covered in hexagrammic warding runes, protecting a psycho-reactive crystalline matrix similar to that found within Force Weapons.

Psychic Dampeners function by attracting any psychic power within their vicinity towards them through use of the runes acid-etched into their surfaces, redirecting it into crystalline matrix where it is safely stored. The amount of energy it can store depends upon the size of the device, but the threshold of power it can contain is finite. As a result, if it does reach it's threshold a Psychic Dampener can be jettisoned or even thrown like a grenade towards the opponents, where it detonates into an explosion of pent-up warp energy.

Individual Iron Warriors or Thorakite Marshals might have smaller variants of this device mounted on their armor, while vehicles such as Tanks and APCs might have larger variants attached directly to their hulls, allowing them a degree of protection against psychic attacks.


Warband Relics


An ancient war machine from the days of the Great Crusade, the Deathknell is a Typhon Heavy Siege Tank, one of the precious few remaining in the galaxy. It is the pride of the Brethren of Thunder's tank armada and the ultimate fortress-breaking weapon, it's mighty Dreadhammer Cannon capable of obliterating all but the most formidable of defenses in a single shot. The dense construction and triple-reinforced hull of the Deathknell not only allows to it wield it's apocalyptic main weapon with impunity, but also makes it an incredibly durable vehicle capable of shrugging off even armor-piecing munitions. The fact that it has survived ten millenniums worth of engagements is a testament to it's resilience.

In addition to it's Dreadhammer Cannon, the Deathknell also sports a pair of sponson-mounted Heavy Bolters, allowing it to mop up any infantry that dare stand in it's way. It is usually at the forefront of any major siege undertaken by the Brethren, it's armament allowing it to blast through any fortifications that stand in it's way and allow the Brethren's forces to advance in it's wake.

Tome Lyssatra

A tome written by none other than Sorakae Vhak himself in the days of the Horus Heresy, the Tome Lyssatra is a compilation of the beliefs, mantras, and doctrines of the Lyssatra warrior-society. It details their first formation with the ranks of the 4th Legion, explains the nature of their creed down to it's most subtle nuances, and remains a source of inspiration for every member of the Brethren of Thunder. To them, this one tome is practically a holy object, it's wisdom only dwarfed by that of it's creator.

Currently, the Tome lies within the vaults of the Battle-Barge Chariot of Lochos, protected inside a custom-made an adimantium vault further reinforced through automated sentry-turrets and conversion shielding. Only Warpsmith Vhak can access the vault, for it's entrance is keyed to his genetics, and therefore only he can withdraw the Tome so that others may learn from it's teachings.

Base of Operations

The Brethren of Thunder are a fleet-based warband, their main base of operations being the ancient Battle-Barge known as the Chariot of Lochos, a vessel nearly as formidable as it is corrupt. It's inner workings and mechanisms have been tampered with to the point where it would make any sane Tech-Priest weep, it's Machine-Spirit ripped from it's datacore and replaced with a host of malefic Cyberdaemons. It's iron-grey hull shows drastic signs of warp-taint, fleshmetal growths sprouting from the adimatium, strange sigils and twisted bone-protrusions decorating it's prow.

The Chariot boasts a terrifying assortment of weaponry, enough to take on a small fleet and emerge victorious, and scores of Thorakite-piloted Hell Blades and Hell Talons lie in wait within it's many hangar bays, ready to assault any and all spacecraft that might threaten the Battle-Barge. Just as the Iron Warriors excel at creating fortresses on planets, the Brethren of Thunder have transformed their vessel into fortress all on it's own.

Notable Members




The Iron Warriors of the Brethren of Thunder still retain their own colors, wearing battleplate the color of burnished iron, trimmed with gold and oftentimes marked with yellow-and-black hazard stripes. However, this appearance is often marred by the sheer number of bionic augmentations, many bizzare in appearance and some even of non-human origin, and oftetimes it is difficult to tell where the flesh begins and the bionics end.

The Thorakites meanwhile typically wear flak armor colored the same burnished color as their master's plate, though hazard markings upon their armor are usually a symbol of rank. Many wear full-face helmets similar in design to Mark IV Power Armor helms, complete with rebreaters and night-vision optics. Some bare bionic augmentations as well, though none are as extensive as their masters'.


The Brethren's symbol is the Iron Warriors' visored skull, superimposed over a pair of crossed lightning bolts, typically colored iron-grey on a field of black. Variations of this symbol can be seen decorating their vehicles, and branded into the flesh of their Thorakite cultists.


Feel free to add your own



"Life, resonating in beats of the heart and flow of blood through one's veins, and Death, resounding from the barrel of the weapon that ends the beating and stops the flow forevermore. The two concepts are inseparable, different sides of the same coin, endlessly repeating over and over throughout the mobius strip that is existence. Why should I struggle against such an elemental principle, when I can revel in it?"
—Sorakae Vhak
"Why? Since when did I need a why? Good destruction shouldn't go to waste."
—Anonymous Thorakite


Feel free to add your own

"Sorakae Vhak. I had doubted that I would ever hear that name again. I suppose there is hope for us traitors yet if that mad weaponsmith has managed to withstand the test of time. Focus fire on the loyalists, I have an old friend to repay."
—Malak Blackspawn ordering his forces to intervene on the side of the Brethren of Thunder during the Burning Crusade[src]
"Ahh Vahk, Patriarch of the Burned Men. I was but a young Techmarine when he and his followers were drawing the ire of the other societies. His crafts are hardly practical, often situational at best. Regardless, much could be learned from... collaboration. "
—Hurlok Zhaz, Chief Warpsmith of the Storm Draugar
"Hm, I find your engines, Warpsmith, more kin and more equal, than I find you. Until you join with the fabric of the warp, you will always be nothing more to me than wasted potential. An empty vessel, waiting, waiting to be filled."
Valkyura Warpschild
"They are the sort of people who would kick down a sand castle just for fun. I wouldn't usually mind... but it was MY sand castle! "
—Calios of the Void Sirens, accounting a possibly fictional event