"Sir! There are too many of them! We have to fall back!"
Hundreds of Astra Militarum soldiers in green flak armor stood in a complex network of crisscrossing trenches. They clutched their lasguns with trembling hands, staring at the clouds of dust kicked up by the approaching xenos tide, where the occasional chitinous silhouette of the swarm was visible. A terrified recruit turned to the captain beside him, shouting to be heard.
"Silence! You coward! Another word of such weakness and I shall execute you on the spot!"
Before the captain could respond, a figure descending from the trench observation post barked the reprimand. He wore the iconic black uniform adorned with exquisite gold and silver braiding, the Aquila of the Imperium gleaming on his collar and chest. Unlike the soldiers' helmets, his red-plumed officer's cap declared his rank: Commissar.
"Commissar, we have only five hundred men. The xenos number at least in the tens of thousands. We cannot hold this line." The captain had seen the rising dust. Even though the Tyranid bio-horrors were still two or three kilometers from the perimeter, the vibration of the earth had already reached them. Facing a battle with zero chance of victory, his loyalty to the Imperium and his faith in the God-Emperor remained, but he did not wish to die without purpose.
"I said: NO RETREAT!" Seeing even the captain waver, the cold-faced Commissar roared in fury.
"Actually, he has a poi—"
BANG!
"DO YOUR DUTY!"
CLANG!
Hearing another voice suggest retreat, the enraged Commissar did not even turn his head. Screaming his rebuke, he drew his bolt pistol and fired a shot upward at an angle.
However, the sound of a richochet caused the Commissar to turn in surprise. He had intended the shot to whistle over the soldiers' heads as a terror tactic, but instead, he saw a Deathwatch Space Marine standing nearby. There was a faint indentation in the center of the Angel of Death's helm; the detonating bolt shell had shrapneled against the ceramite, scraping away the black paint to reveal the dull grey beneath.
For an Astartes, who stood far taller than any mortal, that angled warning shot had struck him square in the face.
The Commissar's face went pale as he realized what he had done. He had opened fire upon one of the Emperor's own Angels of Death.
Emperor, forgive my sin.
The Black Shield warrior, whose pauldrons bore no Chapter iconography, shook his slightly concussed head. He did not punish the mortal officer. This was simply what an Imperial Commissar was meant to do. Without explicit orders, any suggestion of withdrawal was treason; no deserter who abandoned their post could ever escape the final reckoning.
Nevertheless, the situation was dire. Ever since they had last seen those "Iron Men" battling the swarm, the Tyranids had indeed pulled back for a time. But what followed was a series of widespread, small-scale probing attacks. The swarm no longer threw itself in massed waves against the Imperial lines. Instead, it began attacking every planet simultaneously.
Worlds with sufficient defenses could intercept the few mycetic spores that made planetfall, but worlds lacking such protection found themselves in a nightmare. Once these xenos landed, they immediately went to ground, gathering biomass to swell their numbers before launching raids on defensive installations. In regions lacking garrison strength, the swarm grew exponentially until the world was utterly consumed.
Faced with this, the Lord Solar was forced to disperse his gathered strength once more to stabilize critical defensive nodes. Since that time, they had seen no sign of their mechanical "allies" on any battlefield.
They had, however, heard rumors from Ordo Xenos Inquisitors about a lucky individual who had conducted a task on Vorchad III and acquired several suits of exceptionally powerful armor. Most of these were later confiscated by the Adeptus Mechanicus through some convoluted trade, leaving only one for the Inquisitor, a man named Wayne.
Later reports suggested this Inquisitor had been ambushed by a Genestealer Cult while auditing a planetary governor in a front-line Hive. He had single-handedly torn the entire xenos cult, including several Purestrain Genestealers, to shreds, before storming the governor's secret bunker and reducing the traitor and his elite guard to bloody pulp. He had subsequently been charged with heresy, dereliction of duty, and treason.
Because the whereabouts of the "Iron Men" remained unknown, the war grew increasingly chaotic. The swarm opened countless minor fronts, constantly counter-attacking and bleeding the Imperium's attention. Sometimes, a force of thousands would encounter only a handful of xenos. Other times, unlucky detachments of a few hundred would find themselves facing a swarm of tens of thousands.
The sheer volume of engagement zones pushed the Departmento Munitorum to its breaking point; orders could no longer be transmitted effectively. Consequently, the Angels of Death had to be deployed as battlefield commanders in squads of three to five across the fronts to bolster the efficiency of the mortal troops and provide precise tactical judgment.
In the war against the Great Devourer, minimizing casualties was the only way to choke the swarm's growth. If five hundred men were lost, a hundred new xenos would rise from the ground two days later. If fifty thousand were lost, an entire mixed swarm would emerge. If casualties reached the millions and orbital superiority was lost, the world was as good as dead.
"The current situation cannot be resolved by valor alone. I recommend a tactical withdrawal," the Astartes proposed.
With the Angel of Death's backing, the Commissar holstered his bolt pistol and voxed for confirmation. Rear command, judging that the position could not withstand a tens-of-thousands-strong assault, immediately granted the order to retreat.
Seeing the Commissar nod, the Astra Militarum soldiers scrambled out of the trenches and sprinted for the rear, where several Chimera and Gorgon transports sat waiting. As the vehicles roared into motion, kicking up plumes of grit, their pintle-mounted weapons spat fire. The swarm crested the vacated trenches like a chitinous wave.
The Black Shield with the dented helm stood atop a Chimera alongside two battle-brothers from different Chapters, their bolters barking rhythmically into the sea of monsters, occasionally punctuated by the toss of a melta bomb or krak grenade.
"For the Emperor and the Khan!!!"
The vox channel crackled with the joyous war cry of a White Scar.
Yet, battles such as this were being fought every second, on every world across the entire front.