"The blasphemy of the Tyranids is such that only one solution is acceptable. Extermination. There can only be two sides in a fight - choose carefully, lest you and I find ourselves on different sides."
The Tyrannic War Veterans were forged from the remnants of an atrocity committed by Hive Fleet Behemoth against the Ultramarines on their homeworld of Macragge in a series of campaigns collectively known to history as the Battle of Macragge.
During the Battle of Macragge, a good portion of the Chapter was heroically sacrificed to stop the menace of the Great Devourer during its first incursion into the Milky Way Galaxy. Numbering only in their dozens, these Veterans are experts in the art of Tyranid warfare, and have saved many worlds from being completely devoured by the Hive Fleets.
Whenever Tyranid bio-horrors begin to ravage a planet, these Ultramarines can be relied upon to strike a blow back against the swarm. Often in the face of impossible odds, they launch disciplined strikes against monstrous horrors and shred incessant bio-forms with a blaze of bolter fire. The presence of the Tyrannic War Veterans is enough to rouse other Imperial forces to achieve great deeds in their darkest hour.
Though each squad of Tyrannic War Veterans is led by a Sergeant, the entire strike force is commonly directed by Chaplain Ortan Cassius, the Ultramarines' Master of Sanctity and the oldest living member of the Chapter. Scarred by countless conflicts, Cassius leads his Veterans from the front.
He was chosen to lead the Veterans not only because the idea of the strike force was his in the first place, but also because he is still afire with righteous fury at the violence the Tyranids committed against his Chapter during the First Tyrannic War.
To attempt to rid the galaxy of that xenos scourge is a sacred duty for any Ultramarine. To see the Tyranids continue to rampage throughout the galaxy is a reminder of the Ultramarines' ultimate failure to have truly defeated them during the First Tyrannic War.
But for Chaplain Cassius and his strike force, taking the fight to the Tyranids, whenever and wherever they appear, has become a way of life.
"It should convey some measure of the threat that the Tyranids represent to the Emperor's realm that their continued onslaught compelled the most Codex-adherent of all Space Marine Chapters to voluntarily alter their sacred doctrines. The fact of that alteration, of course, also speaks volumes of the Ultramarines' absolute determination to annihilate this rapacious xenos menace."
- —Brother-Sergeant Calistus of the Tyrannic War Veterans
The Battle of Macragge was the greatest test ever faced by the Ultramarines Chapter when they confronted the first invasion of the Milky Way Galaxy by the Tyranids of Hive Fleet Behemoth in 745.M41. Coming from the Eastern Fringes of the galaxy, Hive Fleet Behemoth invaded the Imperium of Man's Ultima Segmentum.
Thankfully, the Ultramarines stood in its way. The Ultramarines were quick to react, and the Ultramarines newly appointed Chapter Master, Marneus Calgar, deployed the Ultramarines Chapter fleet to stop the Tyranid Hive Fleet at the Garden World of Prandium -- the jewel of Ultramar, with gardens and forests of such amazing beauty and genetic craftsmanship that it was considered one of the Wonders of the Imperium -- a world that the Ultramarines were duty-bound to protect.
It was a slaughter. The tactics and strategies decreed by the Codex Astartes, a tome of knowledge created by the Ultramarines' Primarch Roboute Guilliman to govern all aspects of Imperial warfare, did not succeed against the Tyranids.
The harrying strategies of the Ultramarines could not inflict enough damage against the Tyranids, while the close-range passes of Thunderhawks and other Imperial aircraft and vehicles for optimal firepower favoured the Tyranids' mode of attack, since their Spore Cysts and clawed tentacles would burst or tear open many of the ships that went in on the attack.
The Ultramarine fleet had to sacrifice Prandium to consumption by the Hive Fleet. The Chapter needed to adapt and develop new strategies and tactics, even weapons, if they were to be successful against the Tyranid menace. Hit-and-run raids were abandoned in place of concentrated defences and static firepower. This meant that the Ultramarines had to choose a place to defend, and they chose their homeworld of Macragge, the very heart of Ultramar.
Scant solar weeks later, the outrider vessels of the Tyranid fleet attacked Macragge. The alien bio-vessels swept aside attacks by Ultramarines Strike Cruisers and swarmed over the planet below. Soon many thousands of Mycetic Spore-birthed Tyranid beasts scurried and rampaged across Macragge. Deeming that the Tyranid threat was too massive to be opposed piecemeal, Calgar combined his ground forces into three mighty armies.
The primary and secondary taskforces, composed largely of 1st Company Veterans and the regiments of the Ultramaran Planetary Defence Forces, known as the Ultramar Auxilia, bolstered Macragge's polar fortresses against the Tyranid onslaught. Meanwhile, Calgar's taskforce, the largest of the three, performed a series of rearguard actions, attempting to slow the Tyranid advance and eliminate the Hive Mind's synapse-control bioforms.
Calgar achieved great success in the early days of the campaign, buying time with blood for his Battle-Brothers to the north and south. However, the Tyranids kept coming.
In a final climactic battle on Cold Steel Ridge, the Ultramarines rearguard was brutalised by the Tyranid horde and Calgar himself was gravely wounded. Knowing that to remain planetside was to doom his followers to wasteful deaths, Calgar withdrew to the orbiting Battle Barge Octavius.
Refusing all but the most vital medical attention, the Master of Macragge took command of the fleet, and sought a way to save his homeworld from certain destruction. Hours later, the main Tyranid fleet arrived at Macragge. With no sign of reinforcements, Calgar led his fleet in a series of daring attacks, striking at isolated vessels as they spread out to invade Macragge in force.
Caught between the blistering firepower of Macragge's polar fortresses and the vengeful hammer blows of Calgar's fleet, Tyranid vessels were destroyed by the score, but many more yet remained.
As battle raged, the Tyranids unleashed thousands of Mycetic Spores above the vital polar fortresses -- and if the fortresses were taken, Macragge's planetary defence guns would be silenced, and the world left defenceless. So it was that the Tyranids landed in even greater numbers than before, and the fortresses soon found themselves sorely beset.
Their gruesome cargo delivered, the battered Hive Ships retreated from orbit. Trusting to his Ultramarines to keep the fortresses secure, Calgar relentlessly pursued the Tyranid fleet, determined that it would not bring ruin to other worlds.
Never before or since has the valour of the Ultramarines been tested as it was in the defence of Macragge's polar fortresses. The Veteran Space Marines of the 1st Company led the lightly-armed Ultramar Auxilia in a tenacious defence of the fortresses, holding every wall and trench until the last possible moment before it was overrun by the Tyranid swarm.
Slowly the troops withdrew ever deeper into the fortress, while making the Tyranids pay for every single yard of ground they advanced over.
However, the war in space was not yet concluded. Refusing all but the most vital medical aid, Calgar took command of the surviving vessels and began to harry the Hive Fleet as it spread out to surround Macragge. Its forces deployed on the planet's surface, the Hive Mind chose to withdraw its bio-ships from Macragge in order to lure the defending Imperial ships away and thus prevent them from coming to the polar fortresses' aid.
Calgar took the Tyranids' bait, and pursued the Tyranid fleet toward the ringed world of Circe at the edge of the Macragge System. The timely arrival of the Imperial Navy's entire Battlefleet Tempestus from Bakka finally sealed the Tyranids' fate by catching them in a vice between the two fleets.
Even now, the Imperial fleet was overmatched, for the Tyranids were too many. However, the Hive Mind's victory was short-lived. The battle would have been lost save for the heroic sacrifice of the great Battleship Dominus Astra.
Charging into the heart of the Hive Fleet, the huge Emperor-class Battleship detonated its Warp-Drives, creating a Warp vortex that dragged both it and the entire Tyranid fleet to oblivion. With the Hive Fleet destroyed, Calgar's surviving starships came about and roared back to Macragge to try to save the beleaguered polar garrisons.
Through darkness and terrors unimaginable, the 3rd Company finally reached the lower Penitorium where the Astartes defenders had made their last stand. Tyranid bodies were piled six deep around the doors, and within the room a circle of Terminators lay where they had fought back to back. Each had given his life for his brothers. The Ultramarines' 1st Company had been wiped out to the last man.
The Battle of Macragge remains a great source of both sorrow and pride for the Ultramarines. The names of its fallen are commemorated each year by the Chapter at the Feast of Days, their sacrifice remembered throughout Ultramar with honour and gratitude, but the cost had been great. The Ultramarines 1st Company was gone and the 3rd and 7th Companies sorely diminished. It would be many long years before the Chapter could properly replace its losses, but replace them it would, and the Ultramarines would endure.
Conclave of Herra
"The swarm humbled our Chapter in a way no other foe had yet managed, and no other will ever achieve."
In the aftermath of the Battle of Macragge, the Ultramarines were faced with the herculean task of rebuilding their most experienced body of Veteran warriors -- the 1st Company. Responsibility for this undertaking fell to Chaplain Ortan Cassius, whose hatred for the Tyranids and all they had done to the worlds of Mankind knew no bounds.
Cassius petitioned Marneus Calgar for the authorisation to raise a new body of Ultramarines drawn from the ranks of those Astartes who had survived the First Tyrannic War. Only those Space Marines who had been tested like he had could truly understand the threat posed by the Tyranids.
This new cadre was a departure for the Ultramarines, a Chapter for whom such non-Codex specialisation was almost unheard of.
Perhaps not surprisingly, there was resistance to the recognition of Tyrannic War Veterans within the ranks of the Ultramarines. Though the Master of Sanctity himself urged the formation of such squads, many of the Chapter's Captains protested that such a unit was unsanctioned by the Codex Astartes and therefore unthinkable.
Arguments both for and against the formation of Tyrannic War Veteran squads raged back and forth, but no resolution could be reached. Eventually, Marneus Calgar decided that such arguments, while providing much theoretical debate on the origins of the Codex Astartes and the intent of Roboute Guilliman, were ultimately fruitless.
In order to break the deadlock, the Chapter Master decreed that all warriors of the Ultramarines could have their say upon the matter at a great conclave to be held on Macragge following the great Feast of Remembrance, where the Chapter honours those who died to defeat the Tyranids of Hive Fleet Behemoth.
Ultramarines travelled far and wide to attend the Conclave of Herra and Marneus Calgar waited for as many of the Chapter's warriors to arrive as possible before beginning proceedings in the shadow of the great Primarch himself in the Temple of Corrections.
Each warrior was permitted to speak his mind on the formation of the Tyrannic War Veterans unit within the Chapter and many opinions and views were aired before the Chapter Master. Chaplain Cassius and Captain Agemman of the 1st Company spoke passionately of their value, bringing a surviving warrior of the Scythes of the Emperor, Sergeant Remas, before the conclave to speak of what he had seen and learned in battle against the Tyranids.
The conclave continued for many solar months, as warriors who had been unable to reach Macragge before its beginning arrived and spoke their minds on the issue. At long last, Calgar decreed that he had heard all he needed to and retired to his chambers atop the Ultramarines fortress-monastery to ponder the matter.
For many solar days and nights the Chapter Master of the Ultramarines thought of the widely differing views espoused at the conclave, praying and fasting for guidance from Roboute Guilliman and the Emperor. As dawn broke on the morning of the 40th day, Lord Calgar emerged from his chambers as word reached Macragge of Tyranid creatures attacking settlements on the Cardinal World of Espandor -- monsters stranded in the Realm of Ultramar after the battles against Hive Fleet Behemoth.
Calgar took this as a sign from the Emperor and declared before his assembled Astartes that the Tyrannic War Veterans would indeed become part of the Ultramarines' military structure. This new infestation would be their first trial and, should they prove successful, then all would recognise their usefulness.
Cleansing of Espandor
"Permit? There is nothing to permit here. Cassius is indeed correct in declaring that such a force would be in accordance with our primarch's wishes. Therefore Cassius will lead the Veterans, and together they will carry the very spirit of our Chapter."
During the subsequent Cleansing of Espandor, the Tyrannic War Veterans were organised into three detachments by Chaplain Cassius and together he and Captain Agemman led them to the site of the most recent Tyranid attack. Having specially modified their auspexes to detect Tyranid pheromone trails, the Ultramarines were able to track the aliens into the dark depths of the world's primeval forest.
The trail continued for many kilometres, eventually ending at a great, bio-organic structure enmeshed within the trees that resembled a great insect hive.
Hissing Tyranid creatures poured from the hive and attacked the Ultramarines, but with Flamers and disciplined Heavy Bolter fire, the aliens were forced back and the warriors of the Ultramarines pursued them within the blasphemous structure.
Inside was a warren of caves formed from Tyranid biomass, each tunnel a potential hiding place for a Tyranid bioform. With great discipline, the Ultramarines fought downwards through the hive, cleansing and burning everything before them.
At the heart of the hive they discovered a wounded creature that obviously still served as some kind of synpase creature that controlled the lesser beasts. Only its crippling injuries prevented the Tyranids from spreading further across the surface of the planet, but the alien monsters that protected it were no less fierce than any other.
The Tyrannic War Veterans fought their way through the creatures and Captain Agemman himself slew the beast. The expertise learned in previous engagements with the Tyranids proved invaluable, as each Astartes knew precisely where to strike their foes to cause maximum damage and understood how the aliens fought.
Such was their skill and training that not a single Ultramarines warrior was lost in the battle. With the aliens expunged, the hive and the surrounding area was destroyed by a sustained orbital barrage to ensure that no taint from the aliens survived.
Formation of the Tyrannic War Veterans
"Remember the names of the honoured fallen, recall their deeds and know that their sacrifice honours the Chapter. No son of Guilliman could wish for a more glorious death."
Upon returning to Macragge, the value of the Tyrannic War Veterans could now not be doubted and with the Chapter Master's sanction given, for the first time in the Chapter's history, the dictates of the Codex Astartes were re-written, and the elite cadre of Tyrannic War Veterans was incorporated into the military organisation and order of battle of the Ultramarines Chapter.
Chaplain Cassius gathered his corps of Tyrannic War Veterans. Under Cassius' leadership, those Battle-Brothers who had fought the hardest against the Tyranid swarms that had assaulted Macragge were elevated and afforded additional duties, until each was eventually judged worthy of joining the ranks of the slowly reconstituted 1st Company.
These so-called "Tyrannic War Veterans" make up the first and most powerful squads of the Chapter's reformed 1st Company, and are second to no other warriors of the Imperium because of their experience, training and upgraded Power Armour.
Though a minor deviation from the Codex Astartes, Marneus Calgar tolerates his mentor's divergence from its sacred tenets, sensing that someday there shall be a final reckoning between the Ultramarines and the Tyranids, and that Cassius' Tyrannic War Veterans may be the key to final victory.
Soon, the expertise gained from fighting the Tyranids was included within the training of all Space Marines of the Ultramarines Chapter. Those who excelled in this field of warfare are now often seconded to units likely to see action against the Tyranids, in order to further hone their skills.
Cassius' veterans could be forgiven for wondering what fate would meet their order when Roboute Guilliman was resurrected and altered his Codex Astartes. Would he end their organisation? Would he tolerate it? None dared believe he might embrace it -- but that he did.
After learning of the Tyranid threat, Guilliman immediately saw the value of the Tyrannic War Veterans, praising his sons for their adaptability in the face of such a dangerous foe.
With the Primarch's blessing, the Tyrannic War Veterans took to their task with renewed vigour, with ever more Successor Chapters embracing their own Tyranid hunters as a result.
The Tyrannic War Veterans serve in every part of the Chapter, often as squad leaders where they can pass on their knowledge to their Battle-Brothers. Under their command, the expertise they gained at such cost during the Battle of Macragge has been passed on and disseminated throughout the ranks.
Fire support Astartes are taught where to aim their weapons to bring down the mighty warrior beasts of the Tyranids, or how best to use rapid-firing heavy weaponry to hold a seemingly endless swarm at bay.
Battleline warriors are taught the optimum combination of firepower and manoeuvrability, and which creatures to attack to the disrupt the whole.
Close support Space Marines are taught how to engage this most fearsome of close-quarters enemies in the deadly storm of close combat, countering every attack the enemy tries to make and in turn dealing it the killing blow.
While the Tyrannic War Veterans tutor others in their knowledge, they seek also to learn more about the Tyranids. It was the Codex Astartes that provided the inspiration for this quest, as Roboute Guiliman had committed his own wisdom and experience to its pages so that others might learn from his example.
Each squad is composed of a Space Marine Sergeant and four to nine Space Marines, armed with a Bolt Pistol, a special-issue Bolter, Frag and Krak Grenades, wearing their distinct Power Armour displaying Purity Seals and, should they earn it, Terminator Honours.
One squad member may take a Heavy Bolter, while another may take a Flamer, in place of their special-issue Bolter. They may also use a Rhino or Razorback from the Chapter's Armoury for transportation.
Tyrannic War Veterans are specially trained in how to kill Tyranids, both with close-combat and long-range weaponry, by targeting known weak points in the different bioforms' anatomy for maximum penetration and damage.
Tyrannic War Veterans have honed their reflexes to incredible heights to better combat Tyranid warriors in hand-to-hand combat, particularly through the use of Krak Grenades normally reserved only for armoured vehicles.
They also use special Hellfire Rounds in their Heavy Bolters, and are trained to work with other Space Marine squads to bring down both large and small Tyranid creatures.
The Tyrannic War Veterans fight with a mix of close combat weapons and long-range firepower that best exemplifies how to defeat the Tyranids. They carry special ammunition for Heavy Bolters, known as Hellfire Rounds, which were developed by the Magos Biologis of the Adeptus Mechanicus working in tandem with the Ordo Xenos.
These shells are designed to shatter upon impact, shredding their targets with thousands of needles coated with a powerful mutagenic acid that is lethal even to Tyranids. Flamers are an important part of their arsenal, as such indiscriminate weapons are deadlier to the smaller, but no less dangerous, Tyranid organisms.
But firepower alone will never be enough to halt a Tyranid assault, and each warrior is highly trained to recognise and strike weak points in a Tyranid's body. Every warrior has had his reflexes honed to incredible heights, that he might better fight the Tyranids in close combat.
In addition, Tyrannic War Veterans are trained to utilise Krak Grenades in close combat, something normally only possible when attacking armoured vehicles. They have proved that larger Tyranid creatures, those that would normally be too large to defeat with conventional close combat weaponry, can be brought down by the careful placement of a grenade somewhere vital.
Tyrannic War Veterans are trained to work with other squads of Space Marines to utilise their skills most effectively, driving larger broods of Tyranids towards the guns of Devastator Squads or guiding smaller ones onto the blades of Assault Squads.
Having now fought successfully in several major engagements, it would seem the Tyrannic War Veterans are now an established and accepted part of the Ultramarines Chapter.
When the Hive Fleets overwhelm a planet, there are many options available to Imperial Commanders -- the mobilisation of huge swathes of Astra Militarum regiments, fortification of Imperial placements or even Exterminatus.
However, when a planet is of particular importance to a star system, Ultramarines Chapter Master Marneus Calgar mobilises Ortan Cassius' Tyrannic War Veterans, who then deploy from their Strike Cruiser Vengeance of Macragge into a battlezone.
With all the pragmatism and tactical nous of the Ultramarines, these Veterans are trained to deal with any scenario on the ground, and local Imperial officers are often honoured to cooperate with the battle doctrines of these revered warriors.
Whether the planet has a large contingent of domestic planetary defence forces or has only limited numbers garrisoned there, whether they have to deal with harsh environmental conditions or terrain ill-suited to defensive actions, the Tyrannic War Veterans will process and execute a plan to deal appropriately with the Tyranid threat.
Once engaged, the Tyrannic War Veterans smash through seas of chitin in Land Raiders. The vehicles' Heavy Bolters and Lascannons are able to eviscerate broods of Gaunts, fell Hive Tyrants and Tervigons alike.
Once into the thick of battle, the Veterans charge down the vehicles' ramps and continue their slaughter of the hungry bio-forms. Tyrannic War Veterans are trained to read the movement of the swarm and understand the baser xenos instincts, so the Space Marines excel at guiding the battle at range.
However, the Veterans enjoy nothing more than to face the bio-horrors close enough to smell their burning carapaces and spilt ichor. These sensations go some way towards satisfying the Veterans' urge to avenge the warriors of their Chapter's fallen 1st Company.
Over the years, the Tyrannic War Veterans have learnt to observe different behaviours in the Hive Fleets. Whereas the Behemoth preferred blunt attacks, overwhelming planets with Tyranid war beasts, the Kraken proved more insidious.
As a consequence, the strike force has adjusted its tactics. Against the remaining splinters of Hive Fleet Behemoth, Cassius maintains rigorous fortifications on the ground, but often attacks off-world from the Vengeance of Macragge, in order to weaken the coming Tyranid assault.
Against the forces of the Kraken, however, Cassius often takes the fight to the Tyranids themselves. On the Shrine World of Saint Theresta, Cassius led a stealth mission into the capital city's hab shrine.
The Veterans flushed out hordes of the Kraken's Genestealers, who had been skulking within the many hundreds of levels, and burned their rotten forms.
Whether fighting as their own force or assisted by Veterans from other Chapters, Cassius' strike force continues its crusade to save key Imperial worlds from Tyranid invasions. Given the unpredictable presence of the current assault by Hive Fleet Leviathan, there are always a number of vital Imperial planets suffering from the incessant attacks of the swarm.
Cassius' work is endless. Yet it is thought by those Space Marines who sometimes fight alongside the Tyrannic War Veterans that Cassius has observed some pattern in the movement of the Hive Fleets.
With his closest Battle-Brothers, Cassius discusses his prime theory concerning the Leviathan. He is convinced that this Hive Fleet is seeking to cut off the Segmentum Tempestus from the rest of the galaxy in order to create a vast Tyranid breeding ground.
All that remains certain is that few Space Marines are better skilled in the subtleties of warfare against Tyranids than Cassius and his legendary Tyrannic War Veterans.
In the centuries since the First Tyrannic War, those who survived have passed on the grim lessons they have learnt to those Astartes who have not faced the Great Devourer. Since the earliest days of their impromptu brotherhood, it has been a tradition of the Tyrannic War Veterans to teach as much as to fight, spreading hard-won insight amongst Astartes of every Chapter, and to swear the Apocryphon Oath is one more route for this knowledge to be passed on.
Thus it was that the first of the Tyrannic War Veterans presented himself at Watch Fortress Erioch in the Jericho Reach. His duty is to disseminate what he knows of the Tyranids and their methods, tutoring others, even the elite of the Deathwatch, in how best to counter the Hive Fleets' advance.
By joining the Deathwatch, the Tyrannic War Veterans increase their chances of encountering the Tyranids on the field of battle, and in so doing learn more of their enemy's ways. Finally, what he learns of the Tyranids whilst undertaking his Vigil can be taken back with him to his Chapter, disseminating his hard-won knowledge still further.
Several Tyrannic War Veterans are currently serving the Long Watch in the ranks of the Deathwatch of the Jericho Reach. One, Brother Scelus, is considered likely to be granted the rank of Watch Captain, though whether or not he will accept this honour given his need to return to his Chapter and pass on his knowledge remains to be seen.
It was Brother Scelus who mastered the technique of using a cluster of sync-fused Krak Grenades to slay the very largest of Tyranid monstrosities, and he has passed this unique tactic on to several Battle-Brothers he has served alongside.
Other Tyrannic War Veterans have mastered the use of various xenos-keyed poisons, coating their combat blades with deadly venom or delivering them by way of special ammunition.
All of the Tyrannic War Veterans are masters of fighting the Tyranids, and to serve in the same Kill-team as such a warrior is to fight alongside both a trusted Battle-Brother and a masterful tutor in the arts of death.
The work of the Tyrannic War Veterans is never complete against a foe as unyielding as the Tyranids. Cassius' Veterans travel the length and breadth of the galaxy, striking blows against the Hive Fleets whenever the opportunity presents itself. Here is a selection from Imperial records of some of their more famous deeds:
- Tyrannic War Veterans Strike Force Formed (747.M41) - Following the Conclave of Hera and deeds on Espandor, Marneus Calgar sanctions the formal creation of the Tyrannic War Veterans within the Ultramarines Chapter. They commence immediate training under the guidance of Chaplain Ortan Cassius.
- Brettiks's Furnace (867.M41) - On the manufactorum-choked plains of Brettik V, a world that generates Promethium for the sector's starships, the Tyrannic War Veterans set a trap for a swarm of Hive Fleet Kraken. After the Tyranids make planetfall, the Veterans funnel the bioforms through the labyrinthine capital, whose civilian populace was evacuated. Cassius' squad continually baits the swarm until millions of Tyranid creatures are concentrated within the city's streets. Having previously disabled the city's manufactoria, a squad led by Sergeant Trajus detonates the platforms of several drilling rigs and redirects their Promethium flows to flood the streets. The Veterans ignite the rampant creatures with grenade explosions. Though the city becomes uninhabitable, the Tyranids advance no further in the star system.
- Leviathan Maimed (939.M41) - On board the Vengeance of Macragge, Chaplain Cassius tracks down a tendril of Hive Fleet Leviathan passing close to an asteroid belt to enter the star system of Jomm. The Ultramarines Strike Cruiser partners with Battle Barges from the Howling Griffons and Aurora Chapters, and destroys the nearby moon of Vendorak. The resulting explosion sends a shock wave through the asteroid field and its debris crashes down onto the planet. The Hive Fleet is severely depleted by the attack and is consequently unable to reach the planets of Jomm.
- Calgar's Orders (991.M41) - A Genestealer infestation rises on Ichar IV. The Ultramarines, led by Marneus Calgar, engage in a bitter conflict with Hive Fleet Kraken. The Tyrannic War Veterans join the rebuilt -- but under strength -- 1st Company of the UItramarines. Together they help drive the Swarmlord directly into the path of Marneus Calgar, in order for their Chapter Master to exact vengeance for Macragge. Calgar engages in combat with the Swarmlord and eventually slaughters it. The Ultramarines proceed to annihilate every last Genestealer, though they are too late to save the planet.
- The Defence of Saint Tylus (999.M41) - The Tyrannic War Veterans reinforce the Ultramarines 3rd Company on the Shrine World of Saint Tylus in the face of an assault from Hive Fleet Leviathan. Cassius takes grim delight in utilising the aerial superiority of the agile Stormtalons against the swarm. As Gargoyles, winged Hive Tyrants, Sky-Slasher Swarms, Harpies and Hive Crones assault the enormous walls outside the central Hab Cathedral, Stormtalons outflank the masses. The aircraft pummel the hordes with Bolter fire and explode the largest beasts with Skyhammer missiles. As the Leviathan's control quickly wanes, the Veterans roll out through the streets in Land Raiders and obliterate the remaining Tyranids. One of the swiftest victories known against a Hive Fleet assault, this success is attributed to Cassius' innovative tactics.
- Battlefleet Gothic 10 (US), "The Defence of Macragge", pp. 6-10
- Battlefleet Gothic 15 (US), "The Ultramarines", pp. 16-23
- Codex Supplement: Ultramarines (8th Edition), pp. 47, 69
- Codex: Tyranids (5th Edition), pp. 12-15, 57
- Codex: Tyranids (4th Edition), pp. 8-9
- Codex: Space Marines (5th Edition), pp. 32-33, 40, 87
- Dataslate: Tyrannic War Veterans (6th Edition) (Digital Edition), pp. 1-14
- Deathwatch: First Founding, pp. 69-70
- Warhammer 40,000: Apocalypse, pp. 25-32
- Warhammer 40,000 Chapter Approved - The Book of the Astronomican
- Warhammer 40,000: Planetstrike (5th Edition), pg. 54
- White Dwarf 306 (US), "Return to Macragge", pg. 92
- White Dwarf 305 (US), "Purge the Alien - Ultramarines Tyrannic War Veterans" by Graham McNeill, pp. 84-89
- White Dwarf 300 (US), "The Battle Rages On", pg. 168
- White Dwarf 299 (US), "The Battle Rages On", pg. 86
- White Dwarf 298 (US), "The Battle Rages On", pg. 80
- White Dwarf 297 (US), "The Battle Rages On", pg. 82
- White Dwarf 256 (UK), "Codicium Imperialis: Defenders of Ultramar - Volume IX, Part I of the Liber Victorum: Battle of Macragge"
- The Chapter's Due (Novel) by Graham McNeill
- Games Workshop Online Catalogue - Space Marine Ultramarines Tyrannic War Veterans