I don't own Transformers, and I'm fudging my facts here from the various incarnations and what I've read. Forgive the mistakes for the sake of enjoying the story.
His intakes shuddered and expelled dirty smoke on the exhale, smelling of burnt lubricant and burning wires. Which wasn't unexpected as that's what a significant portion of his chest circuits were now. Ratchet's hands and forearm plates were covered in the leaking fluids, the result of tubes rupturing as he prised apart armour and metallic viscera.
Optimus sat with his back against a rolled and wrecked fire truck, one spinning tyre still burning on their only defence against the battle taking place. Ratchet's prophetic warning about this happening at the most dangerous time it possibly could had been apt, and the Autobot leader didn't relish the fact that once the medic was done he'd have to get straight up and bolt. As it was this was as far as he'd been able to get away from the actual fight before his body seized with pain and effort too great to ignore.
"This isn't-it's still too soon," Ratchet shouted to him over a fresh round of explosions, and what sounded like another building giving way. He withdrew his hands, ropes of fluid linking them. "You have to wait."
His shout back was fuelled with a fresh wave of agony, his spark throbbing anew. "There isn't time!" Under his glare Ratchet grudgingly returned his digits to his chest, muttering inaudibly. Optimus shuttered his optics as if it would help block out the sensation, tapping into his communication array. "Ironhide, report."
"Starscream's taking a bath and Bee's down."
"Slag it, Optimus - Ratchet's staying with you."
The feed cut out before he could respond, and Optimus opened his optics when he felt something finally 'give'. Ratchet's gaze met his, tight with concentration and concern. "I'm gonna try moving the Matrix, but I won't if the sparkling's in distress. How does it feel?"
He looked down at himself, mouth a grimace behind the faceplate as he focussed inwards on the other spark, throbbing so hot against his own. How did it feel?
It felt like coming full circle.
"Tell me: how does it feel, Prime?"
The title was drawled and spat down at him, slipping through the dark and dust-filled air. His title. His identity. That to which he had sacrificed everything to honour and uphold, and gladly. The title meant a duty to unite, to resolve, to guide. At this moment, with the collapsed building bearing hot and heavy around this tight cavern of girders and brick, he hated it. It was his lineage that had gotten him into this… situation.
But then, it always got in his vents that way whenever Megatron said it. Particularly when it was with this degree of scubeness, which hadn't been often.
Optimus's optics shuttered briefly, but it did nothing for the view. His vision was filled with darkness, a faint outline of Megatron's form and the wide girder that penetrated through his chest and into the floor, cleaving his left thigh plates open. None of it hurt as much as the tear over his spark chamber, though, where components had been torn out to make room for something new, which the Decepticon had forced inside without finesse. Held seated by the piercing metal, Optimus looked to the Decepticon's optics. "I'll rip out your spark and show you."
A low laugh and Optimus shifted a little, testing to see if anything would give enough to let him up. What made this –infinitely- worse was that it was not the extensive damage or the position of powerless that Megatron was asking him about. The girder had been a violently installed practicality to keep him still, trapped with the Decepticon leader beneath the crumbled building.
They both knew what the lingering question was regarding: the new spark chamber welded against his own inside his butchered chest. And Megatron was genuinely interested to know what that new life felt like.
"How does it feel?"
This time Optimus said nothing, metal groaning as he tried again to free himself from the piercing girder. There was the sound of debris shifting and crunching before Starscream's unmistakable voice slid through the dark.
"Megatron, the Autobots are coming."
"Excellent. Do not engage them. We head back."
Optimus waited for Starscream's inevitable protest, or to rage, or to just go off and fight anyway, but the jet did not. To his surprise, there was a rev of assent and Megatron suddenly loomed over him. The girder twisted as he took it in his large hands, and he roared when it was unceremoniously pulled up and out of him. Sliding sideways, he watched Megatron pull aside parts of the 'ceiling' to pour daylight into their cavern, doubtless to make it easier for him to be found.
"Are you certain this will work?" Starscream asked as he climbed up after his master. "They could just as easily kill it."
Megatron answered looking at Prime, smiling. "They couldn't. It wouldn't be in his nature to let them." His voice took on a tone that Optimus hadn't heard before. "I'll see you in two orns to collect."
Minutes of near silence passed. Optimus's world seemed to shrink to the rattling in his air filters and the steady warm pulse of the new spark's presence against his own. At first he hadn't known what it was – had had no idea that this was what Megatron intended when he backed him into the lobby and promptly detonated carefully pre-placed explosions on the support pillars, bringing the place crashing down around them. Couldn't have guessed any possible reason for the Decepticon wanting them cut off and isolated in a makeshift cell. Then he'd had a girder punched through him to keep him down, which had cut off his wonderings.
There had be no cannon, indeed no violence after Megatron had torn open his pectoral plates, reaching into his spark chamber. The electrical charge had lashed out around his hand as he'd tried to drive his body back and away, but it hadn't helped. After he'd torn his arm motors and a raw handful of non-essential components out, Megatron had reached into his own chest and withdrawn a slither of light. Now he knew it was a spark, barely a day old but strong. He'd watched, helpless, as it went into his own chest, latching onto his own spark chamber.
Such a small thing but impossible not to notice. It was disconcerting and new, but not unpleasant. Pure despite where it had come from. It occupied his whole attention, dragging him into a reverie an inch long and a centimetre wide.
Then, Bumblebee's voice shattered the air.
"I've found him! Get Ratchet!"
I only know that I offlined because my CPU reported it. Two breems. It felt like blinking, and now I keep my optics closed as I let my sensors tell me more. My shoulder motors have been replaced, probably the same ones I had before beaten back into shape from how they ache, much like my chest. But the pain is forgettable for the sake of what throbs deeper. It's established itself already, woven in around my spark to become a part of me.
"Well if that's how it is, why haven't you ripped it out yet?" Ironhide, as impassioned as ever following conflict. I can imagine him at the end of this berth, feet spaced in a battle-ready stance. He stays charged up far longer than necessary, armour still flared though he doesn't realise it.
"It's not as simple as that, and I don't want to do anything until Prime's online." Ratchet sounds... odd. His tone isn't one I recognise, though I know the sound of the wrench he throws in my direction perfectly well. "Which I know you are, oh fearless leader."
I open my optics with a sigh, already wearied from the conversation that hasn't happened yet. And the new drain on my system. Sitting up, I swing my legs to sit on the edge of the berth, gripping it when my joints grind from the rubble dust trapped inside. Ratchet's hand is on my shoulder, preventing me from getting up and tearing open the fresh welds on my chest and leg.
Though I know full well what he's concerned with, my concerns as Prime lie elsewhere. "Were there any casualties?"
"Aside from you?" the medic snaps, though the edge in his voice is missing. "No."
"The 'cons took off when Megatron crawled out of that building he pulled down on you, and the only way they could have made it any more obvious that he wanted us to find you would have been to put a location flare over your head." Ironhide, my oldest friend and comrade, moves to stand beside me as if he doesn't know where to look. "Optimus, I-"
I put a hand to his arm, trying to convey what I don't particularly feel. There's not exactly been much time to adjust. "I'm alright, Ironhide."
He shakes his head and finally looks at me, optics hot. "I swear, I'll do everything but kill him for what he did to you."
Ah. I realise that he mistakenly believes there to have been a defilement when the reality is nowhere near as bad. One look confirms that Ratchet believes the same, and I regard them both seriously. "There wasn't – it's not as bad as you think."
Ironhide's engine rumbles at a pitch I know well. Irritation and frustration, though it's not often directed at me. He's struggling. "You are with sparkling."
I'm glad for the mask shielding my reaction to that frank statement. "It would seem so."
He rolls his optics and backs away with folded arms, moving to face away from me. His shoulders flare even more, and Ratchet steps past him. "Prime, I can't allow this. I can't begin to comprehend why-"
"Because it's going to be strong," I break in, shifting as new aches make themselves known. I feel massively overclocked and overwhelmed by circumstance, but then Ironhide and Ratchet are finding it even harder to process. Freshly reminded, my tone is level. "My lineage as Prime, Megatron's own strengths, they produce a powerful sparkling. But there was no spark-merge," I add for Ironhide's benefit. To my relief he turns, posture relaxing a little.
Ratchet's extrapolated what's happened, optics turning distant as he accesses the infrequently-used information. It's been so long since there were sparklings among us. "He budded a habloid spark and attached it to your own spark chamber, where it bonded and began absorption." His optics refocus on me. "I cannot remove it, but I can render it… inert. It'll be disassembled and reabsorbed into your own systems."
"No," I snap back with more weight than I'd expected. Apparently I've already become protective of its wellbeing. "It's staying where it is, and it's going to live."
"But Optimus, there was no choice," Ironhide bites, all emphasis loaded on that last word.
"But there is now. And it remains - with my consent." It's obvious that it's that this was forced on me that is riling Ironhide more than that the spark is from Megatron, which I understand. If our roles were reversed, I would find my anger rooted in the same place. But this isn't something to be angry about, and convincing them of that is an uphill battle. "Our numbers are so few. Every spark is precious, no matter where it comes from."
Ironhide rumbles grudgingly, his scarred face tight with concern. "What do well tell the others?"
"Nothing. This is a medical matter," Ratchet cuts in, apparently offended by the thought of confidentiality being breached.
"Frag's sake, Ratchet, they're gonna notice."
"Ironhide's right, and soon in battle I will be," I search for an apt word that doesn't sting too greatly, "compromised."
Ratchet snorts, instinctively picking up a welding arc. I'm certain that sometimes he picks up his instruments of threat without realising it. "You think you're going anywhere near the Decepticons like this?"
I find myself smiling a little, albeit bitterly. "If anything this will be an asset." Ironhide understands but Ratchet still looks intent on welding my feet to the berth. "Megatron will not want this sparkling harmed. That's why he wanted me back here, with the best medic keeping things running smoothly."
He scowls, folding his arms. "Flattery will get you nowhere. But you're right: you're going to need near-constant maintenance from the way it's growing already."
The next admission is difficult to say, a darkness on the horizon. "He said that he would be back in two orns to take it."
"My aft – let him try."
I look to Ironhide grateful for the support, though it is still obvious that he does not approve. This is his protective nature – the bodyguard in him. Ratchet makes a low sound of assent, and he's committed as well. "Thank you. For now, we say as little as possible. No one's to know that this… donation is Megatron's, and it would be best to keep this from the humans as well."
"What about Sam and Mikaela?" Ratchet asks, finally setting down the welding arc and producing a multi-tool from his fingers.
"They'd find out somehow – tell them, but as little as the others. Doubtless Sam would find the sparkling's parentage as troubling as Bumblebee would, and likely the twins."
"Right. Ironhide, clear out and break the news." I repress a flinch at his choice of phrase, and then again as he approaches me with the array of micro-welders and snips. "I've got a sparkling to make room for."
"Make room? Ratchet, I'm a great deal larger than every femme I've ever met."
"Yes, but you're a lot denser." At Ironside's chuckle, the medic slaps the back of his head without restraint. "I'll need to make room beneath your spark chamber so that it doesn't completely displace it as it grows. You'll be sacrificing most of your backup systems until it's out, so I want you recharging when I tell you to and in here the second I want you to be."
That sounds horribly impractical. "Ratchet…"
"Don't argue with me on this one," he snaps back, stabbing a finger into my chest directly over the sparkling to underline his point. "My priority is keeping you running. Do as I say, because like it or not your life is going to change. Has changed. Paperwork is going to pile up, duties are going to get delegated, and you are going to put yourself on my table as often as I want you to anyway. Understood?"
I nod and run a hand across my face, pinching the space between my optics. Megatron's handiwork didn't have comfort in mind, and my systems feel tainted somehow, full of rough impurities suggesting that a scrubber's out somewhere. No doubt the least of my physical ailments.
Ratchet's optics flash with a scan, and he gestures for Ironhide to leave. Once the dark mech's gone, he gestures with the handful of tools. "Megatron did a hack job," he grouses, as if insulted to be cleaning up the mess. "Get on your back and I'll fix you up. You'll probably want to be offline for this."
The thought of being unaware whilst Ratchet works around the sparkling causes a flash of panic, even though I've always trusted him implicitly. "No. Leave me conscious."
He pauses and regards me seriously, momentarily absent of his usual attitude. "I'll do everything I can to keep from jeopardising the sparkling now I know you want to keep it."
"I trust you, but I want to stay online."
A grunt, and his optics shutter to magnify as he begins lifting away the armour plates about my chest. I watch his face and can tell that he doesn't agree with this any more than Ironhide does. They see the risks as too great, or perhaps it's just the thought of something from Megatron living amongst us that's rattling them. It doesn't matter, though. I know in my spark that this new life is to be protected, whatever the cost.