Unnamed ultramarine POV
Myself and my brothers marched through the abandoned battle barge intent on exterminating any hostiles. This ship had been marked lost for nearly four decades, only to reappear without any communications nor warp signature. A disturbing revelation. My brother captain walked ahead of us, bearing terminator armour proudly.
We stopped.
All around me bolters clicked upwards, seeking targets in the mist.
A figure stumbled forward, perpendicular to us. I could vaguely make out the faded colours of an ultramarine, but that would be impossible. It jurked, sluggishly, with neither warning nor noise. I could only make out the left side of his body, turned away as he was.
His once blue eyes were cold and lifeless. His platinum-blonde hair faded, and worn. Electrical sparks flared around his torso, crackling and popping occasionally.
Our Captain took a step forward, his assault cannon lowered but still readied for combat.
"Brother... can you hear me?" he called out. For but a moment, there was no sign that we would receive a response.
Suddenly, inhumanly, the face of our brother turned towards us. I could hear the confusion and anger across the vox channels. Its right arm was no longer present, a tentacle with multiple tendrels snaking down his armour. The right side of his face was but bone, twisted with moss, fungi and other bright lifeforms.
His mouth was twisted in a rictus of pain. Requests to engage blared across all channels. Many seemed ready to fire, until a voice broke out through the mist.
A single tear trailed down the still normal face of our brother.
"B-brot-brothers... K-ki-Kill...meeeeeee" It rasped.
The rage felt by my brothers was palpable. Whoever,whatever had done this would die.
It appeared that these were the final words of our brother. Not 10 seconds later, what little light was left in his eyes flickered out; the abomination lumbering forward and unleashing an unholy howl.
Instantly, dozens of bolt rounds for there mark. Its head exploded, its legs collapsing underneath it.
A terminator spoke. "Captain, target eliminated."
"No. Look." Spoke an Interrogator Chaplain.
An armed moved. The former marine, already surviving wounds none could match, pushed itself up from the ground. its head stitching itself back together, its legs a weave of ceramite and corruption.
Its twisted voice could be heard once more.
"Lycaaaaooon's sooooonnnsssssss... Floooooded onnnnnessssss... Tideeee... BEARERS... Allllll willl fallll bennneath the marinnnnes amalgammmm..."
It charged towards our captain. Bolter shots round out from all directions, pounding into every part of the beast's body. But nothing. Rounds ping of as if they were fired by stubbers; alien flesh absorbing any that made contact. I could hear the ra-ta-ta-ta of an assault canon cycling.
But still nothing. Twenty feet away, ten, five.
Nothing. Its tendrils lashed out, crushing the captains assault canon. He responded swiftly; an overhead strike, bringing his thunder hammer down on his target.
But the impossible happened.
It caught the hammer.
With it's bare hand.
It smirked. "IIII hadddd stringgsss but now I'mmmmmm freeeee..."
It tightened its grip, and the head of the hammer shattered.
"Not possible" I heard the captain mutter.
Swiftly, he delivered a punch to the abomination before it could continue. The creature flew 7 meters away before sliding to a stop. bolt rounds rained down upon it, still to no effect.
Nothing happened until one of my brothers unleashed a cleansing stream of molten death from his heavy flamer. Fire spead across its body, until all that was left was molten slag and flames, twinkling like a petty toy.
Nothing could be seen through the flames.
Until an arm shot out, dragging itself forward.
"AHgghhghg... ITGH BURNSHHHS! IT burnss!" It roared.
All that was left from the onslaught was a legless, deformed torso.
But still it dragged itself forward.
The roar of bolters had stilled.
The Captain walked forward.
"Rest, brother." He murmered.
his armoured boot came down upon our once-brother's head.
It finally stilled.
The Chaplain marched forward, circling the corpse.
"This is like no corruption I have ever seen. It does not find its origins in Kaos nor the Tyranids. It is unique. As cowardly as it may sound, I dread the day when the chapter must fight an enemy capable of taking our brothers from us."
I could hear a rumbling. More lumbered out of the mist.
(A/N as this is a prototype tide-marine, Tide hasn't been able to completely destroy the astarte inside. Later on it would be easier.)