Hello! first and foremost, thank you for considering to read my story, it is my first fan fiction, so please Enjoy!

Important Context:

This story is about my two favorite sci-fi universes, Star Trek and Warhammer 40k. Note that the story is told from the perspective of the Warhammer 40k faction, so a basic knowledge of 40k might be necessary to understand what I am talking about. You might want to know some key terms such as Hive city, Space Marine, Dark Angel, Thunderhawk, Lasgun, The Warp, and other such knowledge, but I tried to keep that stuff to a minimum, as I wanted to make this readable to as many people from both fandoms as possible and have no intention of explaining the entire lore of Warhammer 40k or Star Trek, as they are both massive universes. I also tried to be faithful to as much of the existing lore as possible but there might be some errors as I get my Warhammer information from reading the Wiki, not the direct source materiel. Lastly, even if you don't like the story, please give some feedback as I am looking to improve my writing skills. With all of that out of the way, onto the story

The thunderhawk gunship slowly touched down on the surface of its target. The planet had no name, only a number, and nothing lived here, not even a virus. However, Rogue Trader Calvin Host had picked up something interesting. They had originally been in this system only to scout for mining prospects, but on one of the planets in an otherwise barren system, they had detected something peculiar. The planet itself was a dusty rock devoid of anything interesting, save the structure they were about to investigate.

"Any idea what it is?" asked Calvin

"Negative, the structure appears to be a large object, 1.2 kilometers in height, 3 kilometers long, and 3 kilometers wide. Unknown material, scans could not penetrate the surface, nevertheless, it seems to be extremely old, possibly dating back before the time of the imperium". Droned Techpriest Illias in his mechanical voice.

Calvin knew that this object was Alien in origin, and whatever it was, likely contained tech he could sell to the Mechanicus. The priesthood of mars was always hungry for new technology to dissect and replicate. He could smell profit.

The Thunderhawk hit the ground and he and the six guards with him all donned their vac suits. They were necessary since the planet lacked an atmosphere. The techpriest didn't need one because of his many augmentations. They all stepped out of the Thunderhawk and he finally got his first look at the thing, and still had no clue what it could be. The outside looked like a circuit board from a distance, but as he got closer he could tell what he was really seeing. It looked like a jumbled mess of plates, pipes, and machines he had no idea the intended purpose of. And it all seemed in extreme disrepair. It definitely was very old. They walked down the side until they found an entrance. It didn't seem to be an actual entrance, but rather a hole in the side caused by millenia of dust storms on this planet. They turned on their lights and went inside.

It was pitch black and hard to see, but the further they went, the more confused Calvin and his group became. The structure was an endless mess of corridors, crawlspaces, and shafts that their lights couldn't reach the top or bottom of, and the occasional interface. This was all fairly typical, but that's not what worried him. There were plenty of connecting corridors, but they didn't seem to connect anything. There were no rooms built for any specific purpose. No living quarters, labs, workshops, dining areas, or anything of the sort. Then they found it. A massive, open space, at least several hundred meters across, and spanning multiple levels. But that wasn't the part that was interesting. Along the walls, on every level, there were alcoves. Thousands. Tens of thousands. Each one contained a humanoid with cybernetic enhancements. He counted at least fifteen different species inside the alcoves, they all had pale skin. Then one of the soldiers Calvin had brought with him uttered the first words since they had entered the structure:

"What in the name of the Emperor IS this place?"

"Keep yourself together", Calvin Snapped, even though he had plenty of questions of his own. Exiting the massive chamber, they finally stumbled upon something interesting. It appeared to be a reactor of some kind, about chest height, with a four sided pyramid in the middle.

"Take a look at this," Calvin said to his Techpreist. The techpriest loomed over the object, and attempted to find some port of entry, but lacking one, decided to just cut it open.

After a few minutes of poking and prodding, Illias decided the device seemed to be some kind of advanced power generator, but still had no clue how it worked. Then, he made a fatal error. He decided to feed the device some power to see what would happen. The device's pyramid began to glow green, and he became aware of a low hum emitting from the device. Suddenly, the lights in the room they were in kicked on, briefly blinding everyone. Activating this generator was a mistake, as it quickly used its power to activate hundreds of other generators across the ship.

"What did you do?" Calvin demanded.

"I believe I turned it on," replied the techpriest.

More lights clicked on down the halls around them and the Humming intensified. It was at that moment that the techpriest realized he had activated more than just one small generator, he had activated the entire structure.

"We have to get out of here, now." Said the techpriest hastily.

"Why?" asked Calvin.

"Because the whole structure is coming online, and its inhabitants might be as well."

Sure enough, he was right, as they passed through the room of the cyborgs stepped out of his alcove, and turned towards them. The entire party froze. The man began to walk towards them; and everyone raised their weapons. Seemingly undeterred, the man began to continue towards them. Suddenly, there was a flash of red light, and the person's chest exploded, spraying blood and implant parts everywhere as he fell to the ground. The Lasgun had easily punched through the black metal "armor" that the person was wearing on their chest. Calvin didn't even have time to express his extreme displeasure with this turn of events, before more of them started to step out of their alcoves and march towards them. Lasfire flashed again, but these creatures seemed to be protected by some sort of energy field now; he could briefly see the green field flash when the Lasfire struck it. As they drew closer, Calvin drew his power sword and swung it at the nearest cyborg. Up until this point, they had only walked and moved slowly, but this one's arm came up surprisingly fast to catch his attack at the wrist. Then, just as quickly, his other arm came up to his neck, and two flexible tubes sprung from the implant on his hand and pierced his neck. Calvin Host felt cool liquid enter his body as all his muscles involuntarily tightened, then went slack as he collapsed to the ground. From there, he watched them close in on the rest of his group.

Illias bolted through the corridors as fast as his mechanical legs could carry him, and it was fast. He had separated from the rest of the group, knowing that they would end up dead if they went back through the room with the cybernetic men. His cogitators had plotted alternate routes based on the layout of the structure they had explored so far, and they did not fail him. He found the exit, and nearly fell as he approached it because the entire structure had begun to shake. As he emerged he looked back and saw hundreds of thousands of small, no bigger than a dinner plate, machines crawling all over the surface of the structure, repairing it. Pulling plates back into place, welding pipes, and even linking themselves together to cover broken parts of the hull. That is when the structure began to rise out of the ground. To the Techpriest's horror, he finally realized what this thing was. It wasn't a structure, it was a ship. And with the repairs underway, he could see what shape it was, or rather was meant to be, it was a perfect cube. His only words were:

"Omissiah forgive us, what have we done?"

—-

Inquisitor Cassandra Vess sat in the command chair on the bridge of her ship, the Enduring Flame and looked at the blast shields covering the windows out into the warp. They were en route to Nyla after receiving a distress call. The distress call spoke of men with cybernetic implants attacking their world. Nyla was a newly settled agri world with only a little under a quarter of a million inhabitants. Normally, this wouldn't warrant an Inquisitor of her stature, the description of the attacking force sounded like it could be the Adeptus Mechanicus, and if they had attacked a world under the Imperium of Mankind's rule, the implications were massive.

"We have reached our destination, preparing to exit the Immaterium," said the navigator's voice over the vox communicator.

"Alright, All hands prepare to exit the warp" said captain Jonathan Thor to the entire ship over loudspeaker.

The ship rumbled for several seconds as they made the transition into realspace, and the blast doors over the windows on the bridge slowly retracted, giving the inquisitor a view out into the void.

Full scan of the surface, the Inquisitor ordered as they entered orbit over the settlements on Nyla. While the commander of the ship was technically capitan Thor, she was an imperial inquisitor, and everyone had to follow her orders or risk being executed, including the captain.

"That's weird". Said the one of the officers on the bridge, presumably in charge of sensors.

"The planet seems to be deserted, and where all the major settlements should be, there's just, nothing. It looks like they were just scooped up off the surface, there is no evidence to indicate weapons of mass destruction".

It didn't make sense, the only reason the Mecanicus would want this world would either be for natural resources or food production, and the present case hinted at neither of these things. Suddenly, somewhere across the bridge, an alarm started to blare.

"Ship approaching, unknown design or species, definitely Xenotic in origin, and, um.." the sensors officer said

"What?" Asked the Inquisitor

"It appears to be a cube, Madam inquisitor.

"A what?"

"A cube, the ship is a perfect cube".

"Void shields to maximum! All crew battle stations!" shouted Captain Jonathan Thor.

The ship rapidly came out from behind the planet and closed towards them with blistering speed, impossible speed, before slowing just as fast in front of the Enduring Flame. More sensor reports came in, showing the ship was fairly uniform throughout, not showing any distinct features on the inside or outside. It didn't appear to have things like a bridge or a power core.

"Do as the captain says, but hold your fire" said the inquisitor. "We know nothing about this species, perhaps we can find out useful information about them before we engage them". They would learn at least one thing useful about this ship immediately, and that was they had the capability to teleport through void shields as a humanoid with cybernetic implants, including a forearm replaced with a mechanical apparatus with several tools on the end of it and a optical implant over the one of his eyes, and covered in black armor with wires criss crossing across its body materialized on the bridge in a column of swirling green light. The captain immediately unholstered his bolt pistol and fired a round directly into the Xenos's head, spraying blood, bone, metal, and brain matter all over the bridge. The inquisitor let out an exasperated sigh and wiped the gore off her face before saying to the captain: "I was hoping to interrogate that one, looks like that's no longer an option however". She would get another chance as a second, humanoid with eerily similar implants appeared on the bridge right next to the one that had just been killed, Not even batting an eye at his fallen comrade or the inquisitor's demands to surrender, he turned to the console next to him and plugged his forearm implant directly into the servitor and began flipping through files at a breakneck pace, so fast each one was only on the viewscreen for a split second before flipping to the next one. The captain fired his bolt pistol again and other crew members drew their sidearms, but this time the bolt exploded harmlessly off a green force field that materialized to block the shot before turning invisible again. The Xeno finished flipping through files, unplugged itself from the console, and vanished in another column of swirling green light, taking the body of his comrade with him. All of these events had taken place in less than a minute. The inquisitor took a few seconds to consider, she now knew that these were obviously the people that had attacked the planet, and that they were definitely not Adeptus Mechanicus. She opened her mouth to give her next order when she was interrupted by the vox system on the bridge, by what sounded like many mechanical voices speaking in unison.

"We have analyzed your defensive capabilities as to being unable to withstand us resist and you shall be punished"

"Resist?" A confused crew member asked.

Then, a green energy field shot from the surface of the ship and enveloped the Enduring Flame.

"Sir! We're losing void shield strength, the energy field is somehow weakening them!" said a crew member on the bridge.

"Full Reverse", the Inquisitor said.

"We can't move, the energy field is holding us in place!" People on the bridge were becoming increasingly panicked now.

"Fire all forward torpedoes!" Roared Captain Jonathan.

Torpedoes streaked through the void and made contact with the Xenos ship, tearing into it, spraying debris everywhere, and destroying the field emitter. The ship lurched as the ship was freed from its restraints and backed up as fast as they could go.

"Get us to the Manderville point, now!" said the inquisitor, raising her voice for the first time since this encounter had started. The cube started to rotate slowly, as it kept pace with the Enduring Flame. It rotated until an undamaged face of the cube was visible, at which point another, identical energy field enveloped the ship, ceasing its mad dash towards the Manderville point.

"Torpedos! Fire!" Shouted the Captain.

Everyone on the bridge was being a little more frantic now. They were still doing their jobs, and no one dared run in front of an inquisitor, but they had never encountered a ship with this nature or these kinds of abilities, and this caused them to fear. Their fear increased dramatically when the second round of torpedoes exploded against the Xenos ship, and… did absolutely nothing. This was impossible, how was it possible that a ship could be completely unharmed by four torpedoes of an imperial capital ship, especially when it had just proven minutes earlier that it could be damaged by such a weapon. Putting her fear aside, inquisitor Vess made a decision: their only option was to attempt a jump into the warp and pray to the emperor that the other ship deemed it not worth pursuing them. She got a brief stare from the captain when she gave the order, but he quickly realized that with their weapons ineffective, their shields being drained, and being unable to move, they didn't have any other options.

"Sergeant, take us into the warp" ordered the captain quietly as he found something to hold on to. Clouds of warp energy enveloped the ship, and the Enduring flame began to shake, lightly at first, and then it slowly got more intense until people were thrown out of their chairs and klaxons echoed throughout the ship constantly. Sparks flew from ruptured cables in the walls and coolant spilled onto the floor. Inquisitor Voss began to think that she had made a terrible mistake.

Just when she thought the ship couldn't take anymore, almost in an instant, it was over, and the ship stopped shaking.

"Damage report" coughed Captain Johnathan.

One of the officers looked at him.

"It's bad. Multiple hull breaches, most of our weapons and void shields are offline, Gellar fields are barely functional, and.."

"Enough, I get the picture." said the inquisitor.

"DID YOU JUST TAKE US INTO THE WARP!?" Shouted the navigator over the vox.

"Navigator, pleas-"

"Are you INSANE!?"

"Navigator!"

For a second it sounded like he was about to continue his tirade, but then decided better of it.

"Navigator, can you get us back to Izata?". A moment of silence.

"I think so"

"Good, then do it."

After that, Inquisitor Voss went down to the astropath's quarters. She arrived and let herself in with her authorization. The ship's astropath had been sitting at his table, eating some kind of long thin pasta, and he looked like he was about to yell at her to leave until he recognized who had just entered his quarters.

"Lady Inquisitor, I… I did not expect you here, I…" but before he could say anything else she got straight to the point.

"I need to send a high priority message to Admiral Raza at Izata."

—-

Admiral Raza sat in the command chair of his flagship, reading the message he was sent by Inquisitor Voss. Despite the harrowing tale that she described, he was sure that the tale was exaggerated and the heightened security was unnecessary. But he knew that the Inquisition would have his head if he didn't comply with the demands in the message. He had under his command 25 ships. 14 here at Izata, as well as eleven more out on patrol, plus the orbital defense grid, so they would be fine. He gave the order to send out messages to all his ships on patrol to keep an eye out for a ship matching this description, and frankly, the description was what made him most doubt the validity of the message. What kind of ship would be a perfect cube? And how could it move if there was no visible propulsion mechanism? Let alone in the fashion described. He already had to deal with the squad of Dark Angels that had just arrived on Izata, and the Astra Militarum forces, and the PDF forces all competing for influence on how the planet should be defended, and he didn't need the Inquisition to also jump on his back. This was also likely the reason he decided not to tell his colleagues in those branches about the message, because a powerful, unknown Xenos species would only escalate the debate about defense.

A day later, the admiral was sitting on his bridge again, filling out reports and giving menial orders, when a ping came up on the sensor grid around the system. It appeared to be an object with some kind of extremely distorted gravitational field around it, moving far faster than the speed of light. Sensors couldn't make out what it was just yet. He looked at it wide eyed, knowing that if this was a ship, someone had mastered faster than light travel in realspace, bypassing the need to go through the warp. The implication of this was massive, and he knew that he needed to be the one to capture the object. But it seemed that he wouldn't need to go and get it. It was coming to him. Gravitational fields disappeared and the object slowed to about the speed of light. Still blisteringly fast, but not nearly as fast as it had just been going. By now the sensors on all of the ships in the system had been lit up with this object.

"All hands battle stations, prepare the fleet for combat" Ordered Admiral Raza Fleetwide alarms sounded as the object closed in fast, he knew that they had only minutes before it was upon them if it kept its current pace.

"Give me an image of the incoming object". An image popped up on one of the many screens in front of his command chair. It was a picture of a gray dot against a black background.

"Well zoom in you idiot!" The person blew up the image and what he saw shocked him. It was the ship the Inquisitor had described, exactly down to the last detail. He began to get a little nervous as the ships spread out to engage the oncoming ship. If the capabilities of this ship were accurate, and so far they were, this could be a costly battle. As the ship approached a loud collection of robotic voices speaking in unison rang out on every vox frequency:

"We are the Borg, lower your shields and surrender your ships, we will add your technological and biological distinctiveness to our own, your culture will adapt to serve us, resistance is futile".

The captain felt a collective chill go down everyone's spine. Finally, he gave the order, "All ships, fire" torpedoes streaked across the void as fighters and bombers flew from hangar bays to engage the enemy ship. As the ship grew closer, three of those green energy fields described in the report reached out and held each of the lead ships in place. Then came the cutting lasers. The beam of dirty white light plunged into the hull of the first ship, as it seemed from a distance that the pattern it traced across the ship was frantic and random, but it was the opposite. The Borg Cube's advanced sensors told them exactly where to shoot. The beam streaked across the ship, causing overloads, shutdowns, severing key systems, and detonating ammunition and fuel stashes. The ship was crippled, but stayed in one piece. The same could not be said for the beam's next victim, however. Plumes of fire erupted from the second ship and sprayed debris and bodies into the void. The Borg cube didn't waste any time with the third ship, slicing into its engine block and causing an overload. The rear of the ship exploded and the front half lost all power. Three ships had fallen In twenty seconds. Their torpedoes did nothing to the ship, as described in the report, As the cutting laser found its fourth and fifth victims, the ships opened up with their side batteries, throwing in with everything that they had, and started to do some pretty serious damage to the Borg Cube, tearing through the unarmored sides. After the sixth and seventh ships were torn to pieces by the beam, Admiral Rios realized the battle was no longer about capturing the Borg ship for his fame and glory, but about raw survival. And unfortunately, their fortunes were about to get even worse. One by one, the borg cube seemed to become immune to their weapons. Volcano cannons were the first to go, and the massive slugthrowers were the last to go. Then the energy field attached itself to the flagship. People were frantically calling out as their shields were being drained by the field, but Admiral Rios just froze. He knew the battle was lost and his ship was about to be destroyed. He closed his eyes as the cutting beam plunged into his ship's superstructure. Klaxons echoed throughout the ship, and The Admiral was pulled from his chair and sucked out into the vacuum of space.

If you made it here, thanks for reading! if you enjoyed, chapter 2 should be out soon! Some of you Star Trek fans know what the imperium is up against, and that they are in for a rough ride, So see you soon!