Author's notes: This is just a fan story, and thus not a canonical or officially endorsed product by any IP holder and owner.

The story takes place around five years following "After the End". Jonah Orion was possessed by a daemon, but he managed to get it exorcised and thus survived the encounter, if carrying some trauma.
Angelos sent Aramus, Avitus and Thaddeus to help purge the rest of the Chapter while Diomedes, Cyrus and Martellus went on to fight Kyras.
The heroes of the 4th Company were reunited and with the help of Uriel Ventris, went on to fight the Nightbringer as it regenerated feeding on Haelstorm's star.

I explained Gabriel Angelos's primarch size and Terminator backflips as him being given an early, unstable version of the Primaris Upgrade, with him, Jonah and Diomedes surviving the events of Dawn of War 3. Though the franchise may not be so lucky.

For now, there are no plans on additional personnel, as one space marine is a powerful enough fighter in his own right. I will try my best to respect the canon if I can, though some parts of the Chibi series may bleed over.

The Imperial Guard and Eldar are often figured in these strange encounters, so I decided to go with a Space Marine. While the Ynnari Eldar seem to be far more pragmatic and reasonable than the older Eldar iterations, I doubt they are in a formal alliance with the Imperium.

My interpretation on the Primaris Marines is what I would think most "regular" space marines would feel. The Primaris seem as much a product of the Great Crusade as their helms suggest, and thus those not in Primaris only new Chapters would need to adapt to the ways of their brothers.

I went against the full replacement of Astartes by Primaris because I feel like Primaris units are all specialists, and that they can not fully fill out an army. They sorely lack any long range anti tank firepower and their weaponry is almost fully limited to bolt and plasma weapons.
Thus there would still be need for regular marine type squads. Perhaps even for Primaris marines in Tactical like squads, with some carrying bolt rifles, others plasma rifles and some carrying missile launchers.

Thus it seemed logical that even if eventually all marines got upgraded to Primaris, they would keep their old wargear loadout and would try to keep the older Mark VII look, as well as other Chapter specific looks, like Primaris Space Wolves with wolf helmets, Primaris Black Templars with knight helmets, Primaris Imperial Fists with Mark III helmets, Primaris Raven Guard with Mark VI helms and so on. Same would go for their wargear, with some having Aquilas or chapter badges on their breastplace.

The recent release of the Primaris Victrix honour guard actually implies this process, as their helms mirror the eagle helms of both Heresy era and regular Ultramarine honour guards. It makes perfect sense that the Primaris would start to take on the culture of their adoptive chapters and thus modify their wargear to look like it.

He remembered what happened after his unlucky encounter in the Veralis system, and the cataclysmic battle with that most terrible of all the Star Gods.

He looked up at Gabriel Angelos, Chapter Master of his order and knew something was horribly different. Once his equal in stature, the venerable warrior was now a towering giant who could have looked Guilliman himself in the eye. He bore his artificer Terminator armour, a mix of ancient Tartaros and Cataprachtii plates, with the ease and agility that would have outdone all but the swiftest of Eldar Harlequins.

Aramus was dwarfed in the same way he towered over a human. As his Chapter Master told him what transpired in his abscence, his hearts sank with dismay.

Belisarius Cawl. Primaris Astartes. Enhanced Gene-seed. An organ to boost biochemistry. An organ to revive a near dead Astartes. Muscles enhanced with flexible stands of Durasteel, for even if Plasteel and Adamantium were much harder, they were too rigid and too heavy. Towering warriors a head taller than he was, clad in identical rows of Mark X Tacticus armour. Which to him seemed like someone put a Mark IV Maximus helmet on an oversized Mark VIII Errant battle plate, but there was subtle differences. Better protected knees and terminator like waist plates, but less protected joints.

That was not what disquieted him. It was that these new brothers were all alike. There was nothing different about them, they were more akin to Skitarii constructed from a template than an Angel of Death. Constructs made to a uniform pattern, not heroes bearing the deeds of millenia on their unique and sacred wargear.

They were now his brothers, the fore runners of a new army to be born after Cawl returns from Cadia. He swore there and then to the Emperor that he would not be replaced. He would not become one of the identical automatons, one of the identical mass produced horde. He would make Blood Ravens out of these soldiers, warrior heroes who were each a testament to the Imperium's might, bright with the heraldy of the Chapter and the symbols of purity.

It was a slow process, but it gained speed after Chaplain Diomedes returned with Angelos and Jonah from the Acheron system. Bolt Rifles were now cleaned with the proper litanies to the Machine Spirits, and plain Tacticus armour adorned with the purity seals and chapter honours that made each new Primaris brother stand out as a true Astartes, an inheritor to the noblest and holiest of all Imperial institutions.

Brother Sergeant Karolis of the Hellblasters had his helmet altered to match the snarling visage of an Errant helm, Brother Gaius of the Intercessors adorning his Bolt Rifle with an Aquila all by himself. Brother Learus used a Mark III Iron helm, and Brother Victus had the Imperialis on his chestplate replaced with an Aquila.
Golden icons and scripture gleamed where once plain red armour was. Tacticus helmets mixed in with Errant helms, and each Primaris brother was now an individual hero of the Chapter, his armour taking the first steps in becoming a relic in its own right.

Aramus had been proud, proud enough to let Apothecary Medicius try the still experimental Rubicon Primaris on him. It was not the too powerful version that turned Angelos into the size of a primarch and made his body reject his augmetic eye, nor was it the more advanced one that would later turn Calgar into the herald of a new age.

It was designed to let him take the three new Primaris organs, but his stature did not rise to the same level as a true Primaris marine. He was half a head taller, but not a head taller than his regular brothers. Techmarine Martellus refitted his Armour of Glory with enhanced Tacticus systems, adding the heavier limb plating and keeping the advanced joint protection of the artificier made Errant pattern. Named the Mark IX Imperator armour, after another name for the Mark VIII Aquila, it was a template for the old Astartes to join the ranks of the new while still keeping their old wargear that has served for thousands of years and was worn by a hundred heroes of the Imperium for whom the Black Bell of Terra tolled.

This was not just a matter of pride, since Tacticus armour was just as rare as the Errant pattern. However, almost all of his brothers have kept the Mark VII Aquila helmet design, for it was by far the most intimidating of all standard patterns and an Astartes was nothing if not a terror trooper. The second most popular was the Phobos pattern Skull helm of the Reavers, though Aramus had the suspicion that it would have become standards with all types of Space Marine if it was more accessible.

Thus did he become at once a monument to the past, and herald of the future. For as effective as the Primaris formations were, they were more akin to the Eldar Aspect warriors. They excelled at one task, but were less suited for smaller engagements that called for more versatile weaponry. The Lascannons of Devastators and the Power blades of Assault marines would still be needed amongst the stars.

Five years after the waking of the Avenging Son, the Primaris marines and regular Blood Ravens were as one. Most of the brothers were not yet upgraded to the new Gene-seed, but even as the Primaris marines took the grilled helms of the old, so did some of the old officers took to the Tacticus helmets.
Nowdays it was just as common to see a brother in Errant armour with a Tacticus helmet as a Primaris brother in a Tacticus armour with an Errant helmet. It was not just the Blood Ravens. While some Chapters like the Ultramarines strictly kept to separate patterns, most Primaris Black Templars have either donned older crusader helmets, or had their owns modified to reflect the knightly traditions of their Chapter.
Of course not all were satisfied, for the Sons of Corax still worked in their armouries to somehow get a beaked Corvus pattern helm fitted onto a Gravis armour, but without success to date.

The older Chapters with ties to the Great Crusade favoured the Mark IV and Mark X, while the newer ones often kept the intimidating helms that for them represented the Astartes long before their own foundings. There were anomalis of course, like the Charcarodons Astra opting for Mark IV and Mark X whenever it was possible.

None from the past ages of old Earth would have called this anything but a lessening of stagnation, but for the Imperium, it was a flurry of innovation unseen in eleven thousand years.
Terminator brothers were seen with underslung bolters on their Power Fists, and Blood Angel Reavers took to carrying Power Swords to enhance the power of their terrifying ambushes. Space Wolf Inceptors deployed compact, hand held Multi Meltas before dropping from orbit onto cultist tank columns.

Adeptus Custodes fought side by side with Astartes and on rare occasions, daemonic incursions were met with a force of gold and silver, Custodian and Grey Knight fighting together against the forces of the Warp, both uncorruptable and born from the pure stock of the Emperor Himself.

Not every organisation was happy with the newly added forces, old or new. The Sisters of Silence and Sisters of Battle were notorius for their rivalry, calling each others fanatics and soulless abominations. Long abandoned, the Silent Sisterhood believed that the fanatics were unjustly swimming in the riches of the Ecclesiarchy, while the Convents of the Sororitas held the pariahs as a particularly vile form of abomination, forever untouchable by the God Emperor's Light.

The Imperium was riven with strife over the return of Guilliman and the opening of the Cicatrix Maledictum, but the Astartes and Mechanicus were thriving, let loose of their millenia old chains in order to stop the Thirteenth Black Crusade. After all, what mattered the balance of power if Abaddon reached Terra?

The Captain of the Blood Ravens Fourth Company started donning his armour. There were World Eaters to kill just a system away.

The gargantuan, warp forged chain axe of the Kytan Daemon Engine crashed down onto the ground. A split second ago, Captain Aramus had been standing exactly in the same spot that was now an obliterated gash in the rockcrete deep enough for a Guardsman to hide in.

Driven to back to Hive Primus, capital of Lorrax, the World Eaters were bending every effort they could into exacting a tide of blood for their defeat. The Fourth Company of the Blood Ravens kept pushing the blood crazed Berzerkers back and back until the heretical warband made a desperate last stand at the Fields of Piety, which was used in times past as a parade ground for the newly founded local Regiments.

Devastator Squad Avitus was pouring lascannon fire into the behemoth, but the powerful energised lasers only left blasted grooves in its unnaturally resilient hide. Terminator Squad Tarkus was doing what they could to suppress the remaining few Berzerkers, with Squad Thaddeus taking care of any that got too close to the Devastators. Davian Thule stood triumphant upon the wrecked remains of a Chaos land raider, his Powerfists tearing the last of its blasphemeous passangers into atomised dust. Hellblaster squad Karolis poured plasma into a pack of flesh hounds, disintegrating the lesser daemons in a blaze of holy starfire.

Dead World Eaters littered the ground, their armour rent by the fire of the Emperor's Chosen as well as whatever stray heavy weaponry the Guard managed to hit them with. He had kept Astartes casaulities low by letting the Praetorian Guard take the hits from the blood maddened Chaos Marines. The victory would have been flawless... if not for the gigantic walker with the essence of a Bloodthrister bound into its hell forged frame.

For something the size of a large Knight, the Khytan was hellishly fast. A trio of gutted Leman Russes were arranged around it, thrown around by the brutal axe strikes that could have rent a Land Raider clearly in half. He dodged another swing of the monstrous chain axe and fired up with his Volkite Serpenta. The crimson beam of thermal fire hit the infernal walker's faceplate, doing considerable harm to the brass skull decorations but accomplishing nothing else.

The Blade of the Unrelenting slashed out at the left leg joints of the rampaging monster, cleaving through its hellmetal gears with power more often seen in a Thunder Hammer. He barely had time to roll away as the infernal machine roared out in more outrage than pain, blasting hundreds of warp-powered shells after its elusive prey.

Aramus quickly realised that as fast as he was, he was just too slow to get behind the creature. It was a blur of bloody motion, coated with the viscera of an entire Platoon of Guardsmen. He raised his Storm Shield as the barrage got closer, the spray of daemonic rounds taxing the power of his powerpack to its limits. Only the combined protection of his shield and Iron Halo saved him from being reduced to a tattered ribon of ceramite, adamantium and transhuman flesh.

He was running out of time. He quickly stabbed out with his holy Power Sword at the intact leg of the Chaos walker, the blade blessed by Azariah Vidya burning with golden fire as it cleaveed the unclean metal of blood stained pistons. The daemonic machine staggered, and he knew it was now, or never.

Astartes always had a conscious control over their bodies, but this was not total. The Belisarian Furnace was designed to be used upon the brink of death, and not activated whenever someone desired to. In a microsecond, he willed both hearts to stop and hyper adrenaline to release from his altered glands. His vision greyed out for a moment as the new organ kicked in, pumping an overdose of combat hormones and nutrients into his hearts, kickstarting his metabolism.

Already fast beyond the conception of mortal men, the boost delivered to his body sent his superhuman biology into overdrive. As the wounded Chaos machine turned, he ducked a blow from its massive cleaver and lept upon its shoulder in a single bound. His blade lashed out once more, cleaving ruin into the faceplate of the roaring abomination.

Muscles enhanced by flexible yet diamond hard durasteel coils lent every blow the force to cleave through a Tyranid Carnifex's body even without the atom-shredding power field of the holy blade. But this was no mere creature of natural laws, this was a horror crafted in the Daemonic forges of the Dark Mechanicum. Its armour resisted that which no matter ought to resist, for its enchanted material cared not for the bonds between atoms.

Oily gore ran down the ruined face of the bound Bloodthrister, its eyes blinded as it flailed with undimmed fury at the crimson figure standing on its shoulders. He had half a minute before its matter be mended by foul sorcery, which was more than enough to holster his blade to his side and drew a melta bomb. He affixed it between the Kytan's helm and its power plant, setting the detonator with a vox impulse to blow in three seconds. Plenty of time to get far away.

Plenty of time to get far away for an Astartes who is not suddenly pushed into the shoulders of the beast by the handle of chain axe thicker than a mortal's torso. A warcry of glorious victory died before the Captain could utter it. Even his blessed Power armour would be instantly vapourised by the bomb in two seconds, and he knew it. There was no time to do anything else but activate the Teleporter built into his power pack, and the world vanished in a golden flash.

The Kytan stood there for a moment, its axe pushed against its now unoccupied pauldrons, before the melta bomb detonated and the entire torso of the unholy construct evaporated in a nuclear blast hotter than any star.

For a moment, he was at once compressed into a black hole and scattered across dimensions. The Warp howled against his mind, a strain that very few mortals save the most holy of Inquisitors could withstand. Then it was nothing but darkness, and he knew no more.

He awoke with a sudden jolt, coming instantly to full awareness so unlike the grodgy, gradual waking of a baseline human. His Power Armour sent updates to his brain, signalling that the power reserves of the miniature plasma reactor in his backpack were dangerously low, below the five percent margin.
The armour had automatically switched to a power conservation mode. He tried to ping his brothers over the vox, but there was nothing. A wide array search still revealed nothing, and his rebooting autosenses picked up nothing but the rustling of leaves in the wind.

Green lens started to glow with returning power as he beheld the ground below him, or rather, a forest floor covered by reddish grass. His olfactory sensors picked up the myriad scents that were usual for a Terra type forest. This was not the hive world of Lorrax.
The air was too clear. The last forests were cut down on that planet some twenty centuries ago. The gravity of Lorrax was 1.2 Terran standard, this planet's was 0.9.

The mind of an Astartes was faster and sharper than that of a man. The deductions came instantly. He was on a different planet. Teleporter accidents sometimes happened. It could have been worse. He could have ended up blown apart with the Kytan, or fused into the corpse of a fallen Ogryn, a blown up streetcar, or just lost in the Warp for thousands of years, slowly going mad as the Empyrean ate away at his mind.

The Belisarian Furnace was supposed to be activated only in Extremis, and his reckless move had put much strain on even his Astartes physiology. His entire body burned with an agony that even his altered and conditioned mind had trouble fully suppressing. It was like undergoing an amputation over and over again. His head throbbed in a way it never did since he left the mines of Calderis as a boy.

But he was a Space Marine. Pain was an illusion of the senses, and despair was something he could no longer feel. He started to get up, with what would have caused ridicule and catcalls of 'old man' would there have been any Space Wolf nearby to see him in such a state. At least the Iron Halo had protected his armour from damage, but it had also drained it almost fully.

His movements were awkward and heavy, resemblind those of an Inquisitor in training. Any Battle Sister could have gotten up with far more grace and agility, for the warrior nuns of the Emperor were the most elite of any mortal fighting force the Imperium could muster.
The Preysight mode filtered the heat readouts over the night vision image as he looked around, seeing that the forest was what humans would term lovely. It was quiet, peaceful, and quite free of the carnivorous flora found on Death Worlds.

Astartes in general towered over humans in intellect, bar a few Space Wolves, but those made up for it with insane bravery and riding giant wolves to battle. Some Chapters like the Blood Ravens took it even further, making great care that their warriors were as intellectually prepared as they were martially.

Thus Aramus looked up at the sky to get at least a relative bearing upon where he was. The Cicatrix Maledictum was easily visible through the galaxy, since the infernal purplish-black unlight emitted by the Warp Rift did not obey such trivialites as the limit on the speed of light. But all he could see was a shattered moon.

It looked to have been recently blasted apart by a small fleet or a few lesser Cyclonic warheads, the chunks still close to the moon and not having fallen back to it, fallen to the planet, or spread out in a ring. He was no Adept of the Machine god, but it meant that the event was relatively recent, most likely only a few decades old, but most likely less.

First, that infernal warp gate to an abysmal galaxy full of annoying redheaded women, and now this. The Emperor really needed to take better care of him, he thought. With such luck, he could become a honorary Lamenter. No, the Lamenter's Chapter Master. Not that he would ever paint a garish heart symbol on his armour. He was a Blood Raven, the Emperor's Angel of Death, not angel of mercy.

But the Inquisition teaches that every problem is a solution in disguise, so he looked around to see the sky being brighter to what his armour told him was the South.
He started walking towards civilisation, as alert as he could be with his armour slowing him down. He would need to find an electrical outlet soon, because while the power pack's system could absorb sunlight and turn water into hydrogen fuel, that took way too much time. Time he did not have if this planet turned out to be under the sway of Chaos.