Author's Notes- Hello all. I have completed university so I should be able to start writing again now. Other stories should have updates (possible rewrites) soon. Also, I'm looking for a beta if anyone is interested.

Warnings- Major Character Death, violence and Transformers swearing. Future chapters likely to be censored for sexual content- see my archiveofourown (link on my profile) account for my unedited works.

Pairings- Knock Out/Starscream. Past Knock Out/Breakdown, past Megatron/Starscream and hinted Breakdown/Arachnid.

Disclaimer- I do not own Transformers or its characters.

Units of Time:- Astrosecond- 1 second, Klik- 1 minute, Cycle- 1 hour, Orn- 1 day, Decacycle- 1 week, Meta-cycle- 1 month, Solar cycle- 1 year, Vorn- 1 million years.

Italics- Flashbacks/thoughts/memories/link speak.

Bold- Comm speak.

Unbetaed.

All mistakes are my own.

Hope you all enjoy it.


Replacement

Chapter One- Cheater

Knock Out sat on his and Breakdown's berth, servos resting on his knees and silent. His optics lit the dark room, though even that source of light carried a darkness, shadows hovering deep in the ruby depths. His partner was late, very late, and the medic believed with a dread-filled spark that he knew why. He stared at the walls of the room, barely venting, as he replayed the warning a drone had whispered to him from the shadows before scurrying off again…

He has been seen leaving her quarters Sir.

Breakdown was always intrigued by unusual things, had been from when he met Knock Out as an Autobot, and Airachnid could hardly be described as a typical creature. Rare form, rare frame, rare alt-mode, rare faction… She was an anomaly, choosing heavier modes than a femme would normally favour, combining strength with speed rather than simply supporting agility, and one of the few, indeed perhaps the only, femme in their faction. And those observations did not even consider her hybridity, her unique energon…

Next to her, Knock Out was merely a pretty chassis. The medic had never believed his partner would stray after they had been committed to one another for so many vorns, but his previous choices of mate had proven disloyal before, growing tired of either his appearance or his whims and abandoning him, occasionally with some very choice words aimed like arrows at the sport car's spark.

He had thought Breakdown to be different, devoted. They had been a team for so long they were little more than two halves of a whole. They fought together, worked together, played together… It had been that way for vorns on vorns, since after the former Wrecker's defection. Now it seemed Breakdown's helm had been turned at last, by a vile little wretch.

A cycle passed and another, the berth cold beneath him as his claws flexed on the sheets, his spark falling deeper and deeper into his tanks. His optics drifted closed as he heard the outer doors slide open and close again with a click. Standing with a quick ex-vent for courage, he waited for his partner to enter.

Breakdown slipped in, frame clean and seemingly innocent, but his field reeked of a foreign entity, something other. Knock Out's fists clenched, betrayal crashing through him, and stood, storming past his assistant and out the door. Frag Megatron, he was going to race Primus damn it! And maybe put some of his fleshling competition out of the picture permanently, as he couldn't do so for those closer to home, the tyrant would more than likely have his helm for attacking his new first lieutenant. Even if Megatron himself had been ignoring the spider's advances, all his Decepticons were his, and the Warlord wouldn't tolerate even that glitch being killed without his consent. And, even though the mighty Megatron would never admit it, the Decepticon Lord missed his treacherous Seeker; any other mech or femme simply didn't appeal to him, and so Arachnid had gone for the next easiest target in her view to get in the berth.

He got halfway to the groundbridge before he realised that Breakdown hadn't tried to stop him leaving…


Knock Out stayed away for three full orns, answering Soundwave's occasional comm pings with fabricated explanations, but the lack of recrimination from Megatron indicated the communications officer was covering for him. At least for now…

He'd go back when his spark stopped swirling with gnats of rage, when he could confront Breakdown without decapitating the other mech. Slamming round a corner, tyres screaming, he blazed out in front of the others, kicking up dirt to fly in the windscreens of his fellow racers. He laughed as the wheels behind his squealed against the ground, his adversaries momentarily slowing down to clear their glass.

And in those precious few astroseconds, Knock Out was long gone. Engines revving hard as he pushed himself to his limit and beyond, knowing no one was around to see him so late and in the near-impenetrable darkness. No stars, no moon, just quiet and shadows. Peace. A sense of relaxation and something like contentment settling into him; yes, this was his domain, where he was at his best even if he didn't look it. Who needed a partner? He had always done better, felt more secure, on his own anyway. He had taken care of himself for solar cycles after all. And what was the point of a partner in the Decepticon army? They were a liability, an exploitable weakness that could get a mech deactivated!

Much better to be alone, to be self-reliant, then you weren't giving others an unnecessary opportunity to harm you. He didn't need Breakdown… He clamped his processor into that line of thought before his spark could influence, and with that revelation he allowed his mind to go blank and set to pounding the track.

He won, of course, by a ridiculous margin but his paintjob was ruined, streaked with mud and scratches from where other cars had gotten too close, not always accidentally. Heading back into the wooded area the race had taken place in; he drove deep into the undergrowth and settled. He would have to go back in the morning, he knew. The vain mech was almost certain he could return now without harming his former berthmate, but he knew himself well enough to acknowledge that he would have to avoid Airachnid for some time yet, particularly if Breakdown carried on seeing her, formed a long-term relationship…

Bonded.

His spark clenched as his engines hissed. Well, she could keep him! Cheating slagger, they deserved each other! Anger wrapping a protective shield around his life-essence even as it poisoned it, protecting his core, Knock Out dropped into an uneasy recharge.

He managed to rest through the night, with few interruptions. The wind flowed in a susurrus through the trees and the leaves sang quietly together and, apart from the occasional jarring hoot of an owl or screech of an animal roaming the ground, there was serenity. On waking, he dared to transform to stretch his frame out, working kinks out in his back and arms. Bright crimson against greenery was hardly discreet, but it was early, the chances of any fleshling seeing him were almost non-existent and MECH, as far as the Decepticons knew, never inhabited this area. Autobots were never seen around here and Sigma knew where Starscream had buried himself…

Knock Out, processor slightly clearer than the previous night as his recharge had sufficiently defragmented him and served to soothe some of his rage, pushing it down to churn at the bottom of his tanks. As he pushed out his chassis, he caught sight of his finish, streaked and scratched, leaving him almost with the appearance of being disfigured. Grimacing, the CMO decided enough was enough. He refused to allow himself to look this way any longer and didn't care to think about the cycles that he had.

Requesting a groundbridge back to the Nemesis, there was a pause on the other end, but it didn't quite last long enough for the medic to question it before it was opened for him…


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