/This is based on events in Red Vs Blue that were hinted at during the Recovery One series and the Reconstruction Series, namely South Dakota's betrayal of her twin North Dakota. This is obviously not cannon as I own literally nothing whatsoever. I believe all credit for Red Vs Blue goes to Rooster Teeth Productions. Enjoy, and review: all are welcome. If I have messed up in any way, let me know and I'll try my best to fix it./

1:

The Sun hung in the wide blue sky and shone down on the brown artificial stone architecture that lay below the Freelancer twins North and South Dakota, as they ran inhumanly fast along the grassy ridgeline towering over it.
The various walkways, structures, large rocks and boulders would provide cover and give the twins the ability to flank their pursuer.
North was relieved that his AI, Theta, had found this place, because it opened up a new world of tactical options, which he realised minutes previously were going to be the difference between survival and death.

"Is it still following us?" asked South.
"Why, still think you can take it after it just kicked both our asses?" replied North.
"It got the drop on me on me-"
"Yeah, 'cause you went off by yourself. Again."
South just released a sigh of annoyance before asking again: "You think it's still following us?"
"I don't know. Just keep running," North replied, not bothering to lie to his sister.
"What about your motion tracker?" she asked, referring to North's armour enhancement; an enhanced motion tracker that didn't seem to be of much use in this latest engagement.
"It's not picking up anything. It must have countermeasures in place."

His choice of the pronoun 'it' was deliberate; neither of the Dakotas knew what was hunting them. All they knew is that unless they reached the destination below them, their sanctuary, they didn't have a chance against this thing.
"Is this the same thing that killed the three Freelancers this month?" asked South, secretly knowing the answer.
"Your guess is as good as mine South. But I hope you are wrong."

South's armoured feet dug into the earth as she tried to control the speed of her decent as she followed her brother, sliding down the face of the ridge.
Hitting the ground she took up a cover position opposite from North.

"Theta, can you identify the best tactical position for us to stage a defence?" she heard North ask his AI. His AI, since she was overlooked again and again, and thanks to the epsilon incident, her chances of getting an AI were non-existent. She hadn't even been trained to receive one and she exactly knew what that meant. She was never going to get one. An AI, a super smart construct capable of enhancing a Freelancer's strength, speed and reflexes beyond superhuman, while the AI itself could handle everything from tactical analysis and communication to treating wounds remotely. An AI was the ultimate upgrade. An upgrade South would never receive, but her twin already had.
Theta replied: "Certainly. I suggest the structure to your one o'clock. A minimum of three entrances and an elevated position."
The AI might be a curse in this scenario, South thought, after al,l even though North didn't know the truth, she did. This thing wasn't after Freelancers; it was after their AIs and their Armour enhancements.
The two Freelancers began to make progress towards the structure, moving in and out of cover, watching each other's backs and simply knowing and expecting the other's movements only the way twins can.
As they neared the structure, North asked Theta for something else.
"Theta, see what you can do about my motion tracker. I don't want it getting the drop on us."
As Theta said something about a 'diagnostic', South just muttered: "Too late."

2:

Inside the structure, light was surprisingly plentiful, thanks to strategic holes in the stone ceiling. The large structure had only three entrances, one to the left, one to the right and one in the centre which had a walkway to a large circular stone structure in the centre of the area.
"Okay, South you watch that entrance and I'll watch this one. We scan the third every twenty seconds. Sync?" asked North.
"Sync," replied South almost instantaneously.
The two carried out their actions with perfect synchronicity as North asked his AI: "How's the tracker coming along, Theta?"
"There does not appear to be any damage or malfunction to your armour enhancement."
"So it's working? Any contacts?"
"Yes it is working, but unfortunately there seems to be no contacts in the vicinity."
"Damn it," said a frustrated North as he scanned his entrances, rather nervously for a Freelancer.

South noticed this. As his twin she hated being paired with him just because they were twins, it had happened their entire life and in the Freelancer program they were known as colloquially as The Dakotas, but in truth there was no one else she would rather watching her back. North would die for her, he had already proved his willingness to do so if necessary on every operation they ran together. But she honestly didn't know if she could return the favour.
"Anything?" North asked.
"No vis," replied South. "Wait-"
The uncertainty in her voice should have been a giveaway for North, but it was hard to pick up on that over the sound of his sister flying through the air and hitting the wall behind many meters her.

"South!" yelled North as he sprinted forward, shooting at where the white-blur-that-was-hunting-them was, just a fraction of a second ago. A grenade streaked towards North, who barely avoided it mid-stride, leaving it to explode against the wall behind him creating a fourth entrance. After firing three bursts he knew he had hit nothing but air.
"Shit. It's good," muttered South as she picked herself up, before running to North. The two were now back to back looking for their hunter.
"No vis."
"No vis."

Another four grenades struck the stone ceiling above them, exploding and breaking it apart. Large chucks of heavy stone began to fall right next to the Dakotas, way too close for comfort.
"Get down," North ordered South as he put his arm around her head, ever protective of his sister. Although she could easily handle herself, the natural instinct of being a brother was never fully trained out of North.
"Might I suggest moving from this location?" said Theta. "It is now less secure than I previously stated."
"I'm not gonna argue with that logic," replied North as another grenade struck the wall behind him and rubble began to fall from the stone ceiling. "Where to?"
"Now that there is no need to observe the ridgeline I suggest the opposite structure. Use the walkways for the most direct route."
"Out there!" said South, a mixture of evident anger and creeping fear in her voice. "Thanks a lot."
"Glad to be of service," replied the AI, missing the sarcasm completely.
"Okay, I'm in front, you on our six," said North matter-of-factly as the two reloaded, knowing his twin would comply before asking: "Sync?"
"Sync."

And they sprinted toward the high exit, reaching the walkway as the sun decided the hit them harder as punishment for their time indoors. The Dakotas moved fast, but carefully. They scanned and analysed every direction but they couldn't pick out their hunter.
"No vis."
"No vis."
They were halfway across the stone walkway, behind a high stone wall that covered only one side, when it struck again.

3:

Their hunter had moved impossibly fast, keeping its body low and out of sight, before jumping up to the wall covered section of the walkway, grabbing the ledge and using its momentum to swing over to the unblocked other side, landing right between both Dakotas. An impossible manoeuvre for any normal Human, almost child's play for a Freelancer, which the Meta was, or at least, what Agent Maine used to be.
The Dakotas could barely turn before the hunter began to attack. First, it swept South's legs with one of its own, before continuing the same movement and kicking North into the chest, pushing his rifle against him as it did so, to prevent him from getting a shot off.
It turned back to South before she hit the ground and it grabbed her legs. The Meta swung her into her brother, sending them both further along the walkway.
North had rolled backwards onto his ass and fired off a burst at their attacker, but the white blur had already disappeared off the walkway.

The two were back to back again, and advanced into the large circular, roofless structure that lay in the middle between their destination and their previous, now mostly destroyed, position.
It would be too hard to defend against this thing where they were now, as it had too many points to enter from. North knew that they had to move, but he never got the chance to voice this.
The thing was back, or at least its grenades were, and one exploded against the ground in front of North, throwing up enough dust to blind him. He fired off a burst through the smoke and hit nothing, yet again.
Instead he was hit, as the Meta appeared from his high right dropping from the circular structures walls. The kick sent him into the wall, hard enough for him to lose his footing, and his battle rifle. The white blur attacked South as she turned and it batted her rifle from her grasp.
As South managed to land a solitary punch on the Meta, North had also closed the distance. He punched their hunter from behind but it seemingly didn't notice him, let alone feel it.
North and South fought in unison, each striking a different target on this humanoid white blur. It was unable to counter everything, but whatever strikes the Dakotas got through didn't have much, if any, effect.

But they knew each other's moves so well that they fought in perfect unison and that in itself was a threat that few were able to repel. But unfortunately the Meta was included in that select few.
Before North realised what was happening, it was behind him and it shoved him into his twin.
"Switch!" North called out, unable to do anything else. The two spun around each other and as North swung around his sister, as she punched their attacker twice before she tried to kicked it.
As South's leg was diverted away by the Meta, North called "Switch" again, spun back around and landed a one-two before he took a strike to the face and twisted back around his sister as she shouted "Switch".
South launched herself into the air and connected with a flying knee to the Meta's midsection and a simultaneous twin hand smash down on its head. Landing, she tried to punch it, but was parried by the Meta who then struck her painfully into the back, perfectly targeting her kidneys.
North was right behind her and threw a heavy right hand. The Meta sidestepped it, caught him and then swung him into the wall before disappearing from view.
Less than a second later it dropped from the structure again, apparently after swinging itself up and over it, and kicked at the twins. But the Dakotas didn't let their guard down and they fought as one, kicking their hunter mid-air and launching it against the wall.

The Meta bounced off the wall, leaving very large cracks and a huge humanoid shaped dent in the thick stone. And still, it showed no signs of slowing. It landed, rolled once toward the Dakotas, reached its feet it and ran horizontally across the wall, over North and behind South, grabbing her and catapulting her across the circular structure, robbing her handgun as it did so.
It didn't take much for North to deduce its intentions when it raised the pistol in his sister's direction. As fast as could, he lunged at the white armoured hunter. He grabbed its arm and wrenched it into the air, making sure that the handgun fired towards the sky, rather than at his South.

North was now facing off against this thing alone and it was all too clear that he was outmatched. He didn't even have time to release one of his hands from the pistol to strike with, when the Meta punched North into the gut and smashed him into the wall. He heard a loud crack come from inside him and a loud click near his helmet and looked up to see that the Meta had the handgun levelled against his head.
Before the thing finished him off, North could see himself in its huge full faced gold visor. A Freelancer, he thought, it must be a rogue Freelancer.
He knew he was done for, and he was just about to scream for help when South read his mind. A burst of gunfire struck the rogue Freelancer and as South's magazine ran dry, the Meta was gone again.

4:

North picked himself up and he realised that Theta had been screaming in his ear for the last few minutes. Now the AI was saying something about 'broken ribs'. Yeah, as if I didn't already know, thought North.
"We can't beat this thing unless we stick together," he told her as he reclaimed his rifle and reloaded it.
"Hey, I wounded it," she said, pointed to the small patch of blood on the stone. "If I hit it once, I can do it again. We'll either kill it, or send it crying back to whatever shithole it came from."
"I doubt that. It took a full burst and didn't even slow down. It's not leaving until it gets what it wants."

It was at that moment that South realised that her brother was right and for once she had to agree with him. That thing wanted something. And North had the AI, not her. It was him that it wanted. He had done everything in his power to protect her since they were kids. He would die for her. It was something he was prepared to do. She made up her mind. She had an idea and it would work. She knew it would.
"Come on, we need to get to the second structure," said North as he staggered along the walkway. In his injured state, it took him too long to realise he was walking there alone.

Below the circular structure, amongst the tall rocks and boulders, South attached her rifle to her back with the magnetic strips on her armour. She raised her hands, knowing it wouldn't matter if she fought back. She tried it for the last ten minutes after they were originally ambushed and it got her nowhere.
This thing was just too powerful, even for me. But I can still survive this, if my plan works.
It had gotten the drop on her when she abandoned her twin back on the circular structure and she knew it. The Meta was only waiting for the right moment to strike.
"Don't keep a girl waiting," said South, with her usual sarcasm.
Now it was behind her, and had brought the huge curved blade on the end of its grenade launcher over her head in such a position that if it chose to it could just as easily strangle her as decapitate her.
As the Meta lifted her off the ground she still she didn't fight. "I've got a deal." She received no response. "You've taken three AIs before. I know what you want and I don't have it. But he does. And I'll let you take it. All you have to do is leave me go. Easy, huh?"
She was already preparing a way to slip out of its strong hold if it didn't take the deal. She would sprint back to North and claim that the thing had ambushed her. Even now she could hear him calling for her.
But she felt the blade loosen from her throat, and heard a low, gargling, monstrous growl behind her. As intimidating as it was, she didn't leave it affect her. And it was through her absence of true fear that she realised that she heard the sound before. It belonged to a Freelancer who suffered wounds to his throat, and as such could only communicate through growls and his AI.
"Agent Maine?" she asked identifying their hunter for the first time, even though she was technically wrong. Agent Maine was dead, replaced by the Meta.
South felt the blade come away from her throat completely, allowing her to drop to the ground. She turned around just in time to see it heading towards the walkway, heading towards North.

5:

"Theta, contact South," ordered North as he tried nervously to cover the wide area all around him. The painkillers and adrenaline that Theta had supplied would take another minute to kick in at least, and thanks to his broken ribs he could hardly catch his breath.
If he was ambushed here, it was over for him.

"South! South? Respond!"
There was no response as he backed along the walkway towards safety of the far structure.
"If I may, in your condition you need to make it to safety and allow my treatment to take effect before you focus on regrouping-"
"No Theta, she's my sister. I'm not leaving her out here."
"Understood. But I must still insist-"
"Can it. Keep an eye out for contacts and keep trying South."
"Very well."

Just then, North heard something, no that thing, behind him and as fast as he could, he turned around to face it, his rifle ready, his finger on the trigger, his sight true. He was prepared to kill, but that thing was too fast, the hunter was too good, and North's rifle fired a three shot burst into the distance as the rouge Freelancer moved through him and...

He felt a terrible, whit-hot pain in his stomach. North looked down and realised that the rouge Freelancer had used some sort of large blade to cut through him. The blade was hanging off the end of his grenade launcher, like a huge, cruel bayonet. The laceration caused by the knifle was huge and deep. He could hear Theta shouting again. No doubt the AI would do what it could to stop the bleeding, but they both knew it was over.
North sank to his knees. He never felt so weak in his life. He hand unclenched against his will and his rifle dropped off the walkway.
He looked into the distance, looked for his twin. But when his eyes found her, it hurt him much more than the blade did.
She was there, below the walkway staring at him. Her rifle was held by one hand. Panic began to join shock in taking over what was left of North's body and his mind. Why wasn't she shooting? As she walked forward it hit him: she had set him up. She had to. Why else didn't she respond? Why else was she still alive?
His mind couldn't comprehend it. He was sure she had betrayed him, but he couldn't focus on it. As Theta began to fade out again, North coughed and the bottom of his helmet filled with dark, thick blood.
The sun was still shinning as strong as ever, but North was quickly fading. He tried to contact South, but immediately forgot what he was doing. He heard Theta speak again and fade out, momentarily forgetting he had an AI. He managed a thought; A lot of good it did me. It's over.
He cocked his head to his left and saw that the white armoured Freelancer was next to him, the knifle raised up in the air, angled towards the male Dakota twin. North knew what was coming next.

South looked at her brother, her twin and swallowed hard. She condemned him to death. South could hear his recovery beacon alarm go off in her ear but she quickly silenced it. She watched as the Meta raised his bladed weapon up and brought it down into the kneeling North's chest, through his torso and out his back, before ripping the bayonet back out. The knifle was soaked in North's dark, red blood.
North Dakota hit the stone walkway and lay motionless.

6:

Only a moment of motionless was allowed to set in before South walked up the stone ramp, surprised by how little she felt for her actions. Instead she felt excitement and anxiety, as the realisation set in that she was so close to an unprotected AI. It was within her grasp. She just had to get close and put a bullet into Maine.
The rogue Freelancer was now doing something to North's armour, undoubtedly searching for Theta. South came closer...
The Meta still didn't notice her...
She pulled her pistol...
Far too quick for even a Freelancer to react, the Meta had grabbed her arm as she pulled the trigger. The bullet cleanly struck his shoulder.
South expected him to weaken and allow her to take advantage. But all he did was growl. She managed to catch a glimpse of the damaged components of the Meta's armour from her earlier attempts, before the rogue Freelancer seized her hand and knocked her out with her own sidearm.

******************************Two Hours Later**************************************

When she woke, the first thing she did was check her brother's body for his AI, but as expected, she found nothing. She was confused because she didn't still didn't really feel anything as she stared at her twin's body. He had died so she could live. It was going to happen sooner or later, she thought.

The main thing was that she was still alive. That's all that mattered to her now. She would have another chance to get herself an AI. Maybe with North gone Command would try to fill the gap?
She then reported to Command and told them about their experience against Agent Maine, confirming the rumours that he was rogue and that he was the one killing Freelancers for their AIs and armour enhancements. She omitted, of course, her betrayal of North and let them assume that she was only spared because she didn't have an AI, which was true enough.

As she expected and hoped for after she finished her report, she was given a reward. Unexpectedly she would have to work for it.
"Another Recovery Agent is being dispatched to clean up Agent North. We need to run an operation against him. You will handle this."
"And why would I do that?" inquired South.
"Because it's an order, South. And upon successful completion we'll have you trained and certified for your own AI. We know how much you want one, Agent South."
And there it was, her second chance.
"Alright. But tricking a Recovery Agent won't be easy."
"Actually, I beg to differ," as the complete contents of a file on Recover One began to fill South's HUD.

*****************************Another Six Hours Later**********************************

"South? South? Are you alright?" asked a familiar voice. She pretended to wake and began to get off the ground. Time to begin her mission. "Are you alright?"
"Yeah..." she replied, feigning confusion.
"I have some bad news. I'm afraid your brother is dead," said the Freelancer next to her, he was wearing full armour with a grey and yellow colour scheme.
"What? No..." she said as she glanced to her brother's lifeless body, his armoured shell just feet away.
"I'm sorry."
She paused for a full minute and hoped this Freelancer would assume that the emotion had momentarily gotten the better of her. "Damn it. Who...Who are you?" she asked, knowing the answer: the objective, the Freelancer I need to trick.
"Agent Washington," came the reply. "What happened here?"