A/N: I know, I shouldn't be starting another story because I update too slowly already but sometime a few months ago I got to thinking about why Sideswipe was on Earth and Sunstreaker wasn't in RotF. Then I got this general idea in my head and through a series of what if this happened instead I eventually came up with this. I didn't mean to actually type it out at first but it's been bugging me nonstop since I thought of it so… here it is. Hope you like it! Disclaimer: I don't own Transformers

This was wrong. The whole situation was completely wrong. It was a simple trip between bases. They weren't even leaving Autobot territory. Prowl, Sideswipe and Sunstreaker had been contacted by Optimus Prime with a request to transfer to the base by Tyger Pax. It couldn't even be called a mission and yet…

The ambush was completely unexpected. By both sides. A group of Decepticon scouts had been using a little known path to try and confirm or deny certain suspicions about Tyger Pax; the path cut across the one the three Autobots had been using as a shortcut to the base. Neither side had let themselves be caught off guard for long. The fight was five Decepticon scouts versus the Autobot's debatably best front line warriors and their head tactician. It should have been easy. In fact it was, until they were down to two. Sideswipe and Sunstreaker took one while Prowl took the other.

The twins fought in complete synchronization and the Decepticon didn't stand a chance. Within moments Sunstreaker was using one of Sideswipe's swords to strike the killing blow. He made to hand his brother's sword back when extreme pain tore through the open twin bond. Prowl's opponent had been aiming for the tactician's spark but had missed. It was sheer luck on the Decepticon's part that it hit Sideswipe's instead.

Sunstreaker threw the sword at the Decepticon hard enough for it to completely fly through him and imbed itself into the structure behind him. He didn't even notice as he scrambled to grab his brother; both physically and over the twin bond. He futilely attempted to keep a hold on the other half of his quickly unraveling spark. Sunstreaker was pretty sure he was shouting. He wasn't aware what or at who, completely engrossed in not letting go of Sideswipe's spark. He truly became desperate when he felt an outside presence gently grab the spark and begin to pull it away from him. He put his entire being into clinging to the last thread of Sideswipe's spark that was still in reach.

"You're going to have to let go." Sunstreaker's grip didn't waver as he looked up at the speaker; a silver femme, covered in the blue runes of the Allspark. She was cradling something in her servos. Sunstreaker was immediately able to identify it as Sideswipe's spark. Tightening his grip he merely shook his helm. A small part of him pointed out that the femme in front of him was most likely the Allspark and that he was disobeying his life-giver. The rest of him, didn't care.

"You have to let go." Another shake of his helm. She looked like she was going to repeat her statement again when he interrupted.

"Please, this is my twin's spark, the other half of my own. You can't… you can't take him from me!" The Allspark looked down at the dim, flickering spark in her servos.

"If I don't do something with his spark then it will fade away."

"Then give him back to me! Please, I'll do anything!" The Allspark looked conflicted hesitating to say what she had to.

"I can't, the body you're holding is a dead one and putting a spark in it wouldn't change that, but…"

"But? But what? I mean it when I say anything!" The Allspark shifted her grip to more securely hold Sideswipe's spark. She looked conflicted.

"So many have died because of your war, if I gave one life back… would it really be that bad?" She glanced up at Sunstreaker obviously guilty. "Even if I did give you his spark back I don't know if you'd like it." At Sunstreaker's –stunned? angry? hurt? There were too many emotions to tell– look she continued. "No matter how I give him back he would have to start over. You'd have to take care of and protect him. It wouldn't be the equal relationship you've always known anymore. He would grow up a completely different life from the first one that you remember and as a result he could end up somewhat different. And that's not even considering the things I can't tell you."

"I understand that things will change. I don't care if he'll be a little different or if I'll have to protect him. I don't care if I have to raise him, just give him back!" There was a long pause before the Allspark responded.

"I'm sorry," she whispered, "but there are rules that I have to follow." Looking almost miserable she mumbled out. "You're going to have to let go."

"No! Please, you don't understand!" And with that he felt her tear away that last strand of Sideswipe's spark from his own. He gasped at the burning pain that seemed to transcend into the physical world before an intense feeling of empty washed over his spark and he was falling into nothing. He barely registered the errors that rapidly began popping up on his HUD. Looking up he saw the Allspark fade away. He managed to murmur a weak 'no' before his world turned dark as stasis claimed him.

XoXoXoX

When he next woke up Sunstreaker was in on a berth in a med bay, most likely in the base by Tyger Pax. He felt empty, incomplete, the twin bond had been the first thing he'd been aware of when he originally onlined, and had been a constant since. Knowing what would happen he tried to reach out only to be met by an empty nothing. It was an acute nothing that burned to touch and plagued his very being. There were rumors that when one twin died the other soon followed. Sunstreaker believed them. He entertained the idea of taking steps join Sideswipe and end the nothing but immediately berated himself. Sideswipe would have beaten him for thinking like that. But Sideswipe wasn't here anymore, just this awful nothing.

A hand fell on his shoulder. He should have been surprised since he'd thought he'd been alone but the nothing was rather numbing. Sunstreaker onlined his optics and looked up, it was Ratchet.

"Prowl told me what happened." Prowl and Ratchet had practically raised them. It had to hurt them too to know that Sideswipe was gone (but they'd never know the nothing that Sunstreaker felt). Sunstreaker could hear the, 'I'm sorry' and the,' I wish there was something I could do' in the simple statement dripping with sorrow. He tried to force himself to respond.

"All I feel is nothing." Not what he'd meant to say but as it was true he let it be. Ratchet looked away, unable to meet his gaze. He seemed to be looking for the right words. When he was unable to come up with them he switched topics

"Prowl told me you had a conversation with someone that as far as he could tell wasn't there."

"The Allspark" Sunstreaker responded simply. There was an uncomfortable pause.

"You've been in stasis a full 3 joors since… then. Though considering the circumstances I'm surprised it wasn't a lot longer." Sunstreaker stared blankly up at him. "Prowl wanted me to make sure you got these." Sideswipe's swords, Ratchet handed them over. Sunstreaker immediately subspaced them. Later, he would get Ratchet to incorporate them into his systems the same way Sideswipe had had them, for now he didn't need any more reminders that Sideswipe was gone. Ratchet held one of Sunstreaker's servos, something Sunstreaker normally wouldn't have allowed. "While you were out there was an attack on Tyger Pax, where we were keeping the cube." So that's why they'd been reassigned. "It was launched into space to prevent it from falling into Decepticon hands." Sunstreaker's hand tightened on Ratchet's. The Allspark was gone. "Prime put together a small team to go after it. You have been added to it." Sunstreaker nodded, unable to do much else through the nothing. He slowly sat up and let go of Ratchet's hand, only to cling to him. Sideswipe had always been the clingy, touchy-feely one. But right now Sunstreaker just need the assurance that someone else was there. And though there wasn't even a caretaker bond between the two, Ratchet was the best he was going to get right now. There were no words that would help this situation, so none were said. It was a long time before they moved from that position; Prowl joining them and offering his silent support at one point. No one else witness to the three bots mourning the loss of a loved one.

A/N: Um, so Yeah I hope you like this and it turns out well…