I'm lacking motivation to keep writing this despite having spent so much time on it, so I'm forcing myself to post the only scene I can. Thus this is short.
Pressure.
It's all encompassing, forcing a mind once capable of extraordinary feats of power to submit and acknowledge nothing but itself. All other thought simply ceases to exist amongst that sensation of crushing numbness licking at the edges of his processor. The feeble recognition of his impending doom is smothered into the background along with the rest of his existence.
A coffin of earth welcomes his twisted frame in its demure embrace. Comforting, pleasant even, if not for the soft threatening creaks of his leaking plating, and that strange echo of fear throughout his spark. His frame mangled and utterly wrong should have lacked the ability to process pain, yet he felt it straining against his spark, almost desperately. Frantic thoughts-not his own but there's no shock at that-yearn for attention from the competing pressure drowning out any coherence.
The din of buried voices, muffled by walls of stone, reaches out and mocks him with apprehensive tones. Relief tinges their minds far more audible than their words. It irks him, that even in the throes of death he'd never know silence. Distress is pinged his way fervently, and the muted voices transition into shouts. Absently he notes the familiar noise of blaster fire as it sounds once, then twice. It's followed by the shouts fading back into hushed words. Beyond his tomb an odd sense of guilt is shared by those minds, seeping into his own. 'Poor thing, probably doesn't know what to do without it's master.'
Clarity strikes him in a distant wave, rolling through his processor with a sickening snap of dread.
A cave in, no doubt the Autobot's fault, had resulted in him being pinned under an unquantified amount of sifting sediment and rock. It might as well been an entire mountain according to his thoroughly compressed sensors. The extent of his damage was unknown, the near entirety of his frame incapable of sensory input. Visor likely shattered beyond the realm of auto-repair prevented any sort of visual evaluation. However, he wasn't naive enough to conclude his condition was anything but critical. Laserbeak had been deployed beforehand, and apparently had not met the same fate as her host. The brief solace he felt at that soured when he realized she'd likely offline slowly once his own spark sputtered out. That is if the Autobots had not already decided to kill the symbiont themselves, it would be a merciful end in comparison. Yet, mercy was unlikely. They thought of Laserbeak as nothing but a drone, and soft as the Autobots were when had they ever shown mercy toward something they believed to be unfeeling?
Anger sets his spark ablaze. The idea of his last symbiont suffering alone until her untimely end spurs the dying mech into action.
He claws forth with his mind with the intent to tear through the Autobot's processors before the allspark could claim him, but...
Cowards.
They were gone. None had bothered to confirm his death. Left for dead by the Autobots, ruefully he wondered why that surprised him. With their absence came the awareness that he no longer desired the silence granted to him. Energon levels ping critical. He struggles to divert his remaining energon to vital systems as it continues to spill from his waning frame in slow sputtering rivlets. Something loses to the swell of pressure around him, and gives in with a weak crunch.
Laserbeak's presence stirs dimly.
He calls out over their bond, her fear greets him, and he's selfishly comforted by the fact he wasn't dying in complete solitude. Dully, through the haze of his systems offlining he hopes she dies quickly.
With that last thought Soundwave's awareness of the outside world ceases, leaving his downed symbiont as the sole witness to the shadows lurking ever closer to her master's tomb.
Death had not found them yet, but someone else did.