Part One: Among the Stones Thrown Before the Tide ...

(A-N: Canon compliant Fem!Shepard, Shakarian, colonist, war hero, infiltrator ... right up until the race for the beam to the Citadel.)

Fewer things made Urdnot Wrex happier than explosions tearing apart the world around him. The bass notes of heavy munitions rumbling beneath the staccato beat of assault rifles, the harsh counterpoint of shotguns belching death, the unearthly thrum-whomp of singularities detonating. No, nowhere filled him with greater joy and exhilaration than standing at the head of a glorious orchestra of wanton destruction.

The Urdnot clan leader took a deep breath of smoke and chaos, striding along the line of his troops, all bloodied and magnificent in their rage. "We hold." He shouted to be heard over the shitstorm. "Krogan don't run, they hold back the horde." Gesturing away from the beam, toward the city, he laughed, low and threatening, as Reaper ground troops swarmed out of the buildings.

"Captains! Hold here! Give the crazed pyjaks their chance to get to the beam." When they roared their acknowledgement, he turned to his squad of ten. "Our battle is getting Shepard to the Citadel to end this war!"

Below his position on the ridge, across the open wasteland around the beam, humans, turians, and asari raced toward the pillar of white light, dodging the enemy's massive lasers and the death throes of their own equipment. Reapers of every size landed, the ground quaking beneath them as their massive red lasers carved up the galaxy's few remaining warriors. Tanks, APCs, even gunships crashed and exploded, adding death on top of death, layering it thick and grisly.

What a tremendous day to be alive.

In the center of the field, Wrex lost sight of the one body he'd refused to take his eyes off of since the beginning: the one he'd sworn his life to protect. A tank exploded, spinning through the air, arcing with a dancer's grace before it impacted, cloaking Commander Jane Shepard and her tiny squad in flame. Uttering an enraged bellow of denial, Wrex charged, slamming through husks, cannibals and marauders like a wrecking ball.

"I am Urdnot Wrex!" He paused, massive chest heaving, his entire body thrumming with the four beat battle song of his pounding hearts. "Leader of the united krogan clans!" He roared a challenge at a banshee, sent a warp flying at it, and charged in the wake of his attack. The banshee crumpled in the onslaught, broken like a toy in the hands of an overeager child. "And I will crush you all."

He spotted Shepard helping Garrus limp toward the Normandy as the frigate flew in, tiny against the Reapers that stomped across the ground like ancient gods. The ship hovered above the destruction and lowered its ramp. Was Shepard leaving? No! He roared his bloodlust and ferocious challenge. His blood sister would never run from battle, not if he had to carry her until one or both of them died. Maintaining his charge, he raced toward the little ship, dividing his krogan to cover his flanks.

Shotguns thundered, a constant, chaotic storm, but his orders boomed out over the madness. "Barl, left flank, hold back those brutes!" He stabbed a finger toward an advancing line of the abominations. "Crel, clear me a path down the middle!"

His troops split, and a vicious smile slashed across Wrex's face at the sheer beauty of their brutality. No one could stand against the free krogan or those with whom they shed blood!

The Normandy's thrusters kicked in, maneuvering the frigate clear of the ground. It swept into the sky, explosions painting its ascension in hues of blood and fire. Wrex took a breath to curse the crew for deserting them, but then he caught sight of a small figure, a frail insect racing amidst the giants. When his roar cut from his throat, it came out filled with awe, a wordless cry of devotion to a sister of blood and heart if not of birth.

If it proved to be the last act of Urdnot Wrex's life, he'd make sure Shepard made it to that beam. What more glory could any krogan ask for? As his sons and daughters took their place among the new galactic order, they would sing songs of their father and his glorious, bloody end … how he laughed as he ripped the heads from Reaper monsters. And he would have sons and daughters thanks to that tiny warrior and her massive heart.

The ground trembled beneath another half dozen of the capital Reapers landing, their numbers laying waste to the allied troops. Lasers carved canyons across the ground, splitting the earth open and devouring everything in their path.

But not Urdnot Wrex! Not that day! Fury lent him grace as he dodged laser strike after laser strike, his eyes never leaving Shepard. Steadily, muscles burning, lungs heaving, he gained ground on her until she ran only a few arm lengths away.

Brilliant, crimson light blinded him, a blast of impossible heat and explosive force flinging him through the air as easily as he kicked a pyjak out of his path. His barriers crumbled, and his armour melted into slag that burned through his skin and into his flesh. Pain screamed, turning his vision as black as his charred hide, but then it vanished, driven out by the rage that flooded his veins, setting fire to his body from the inside. When he roared, mindless fury shattered the eerie silence. He staggered to his feet, dragging himself on all fours, his single working arm keeping him from toppling over. Only one thought remained in his head as the blood rage covered the agony of injuries reversing in slow motion: Shepard must reach the beam.

He could stand without bracing himself by the time he found her, but only the one arm managed enough strength to lift her burned and unconscious form. Draping her over his elbow like a towel, he staggered on, gradually gaining momentum as the billion stinging wasps trapped inside his body did their work repairing his limbs and the damage done to his internal organs and spine. By the time the small cluster of husks scrambled out of one of the pits carved by Harbinger's laser, he'd reached charge speed, and pieces of them returned to the pit from where they came.

He barely registered the marauder before it turned to muck beneath his feet, then brilliant white light tore him from the earth and flung him through the airless void, a sensation that made him wonder how many of his parts and pieces had been left behind.

"Wrex?"

Dead bodies. Rotting bodies lay strewn around him, heaped and stinking, mouldering refuse. The stench filled his head and siphoned down into his gut, but he blocked it out. He'd smelled worse, and air circulated from somewhere. Once he got up and lifted his face above the rotting puddles of flesh, it should fade somewhat. Dragging himself up out of the putrid slime, he crawled over to where the floor was halfway clear and flopped over onto one hip.

"Wrex?"

He didn't recognize the voice, small and broken, haggard and twisted, but he recognized the pile of burned armour lying a metre or so away. "Shepard?"

"Yeah, it's me. Or some of me." A laugh as small and broken as her voice gave him some hope as he crawled to her side. "I'm fucked up, Wrex. Pretty damned fucked up, but we've got a job to do." Shepard lifted her head and yanked her shoulder underneath her. "Is my belt pouch still there?"

He looked. It was melted into her armour, but fairly intact. "Medigel?" he asked, already opening it.

"As much as I've got. Just keep sticking it to me." She chuckled again and let her head hang from her neck, her forehead pressed to the floor. "Never thought I'd ask you to do that, did you?"

The injector port on her armour had been melted away, along with some of her arm, so he jabbed the medigel straight into a bare patch on her exposed hip. "Never thought I'd be looking at your naked rear, either, Shepard. That's more Garrus's battlefield." He administered four more shots and one of painkillers, then heaved himself up and held out a hand. "Come on, Shepard. Let's end this."

She grabbed his hand, her grip still strong, but it took him to haul her up. After limping three steps, she stopped and looked at him. "You look rough; are you up to carrying me? If I walk, it's going to take us a week to get anywhere."

He tested both arms and, finding the second healed enough to lift her, seated her in the crook of his elbow. She wrapped one arm around his hump, clinging to what remained of his armour like the pyjak she was, and held out a hand. "Give me a pistol, just in case."

He did as she said, arming himself with his shotgun. "Never thought I'd live to see the day that you let someone carry you, Shepard." Looking around, he spotted a thin path through the bodies that ended at a door fifteen or so metres ahead. "That way?"

She nodded. "Yeah."

He staggered a little, struggling to find his balance through his injuries and Shepard's added weight, slight though it was. The floor, slippery with the waste of the Citadel's former occupants didn't help. Along both sides of the path, Keepers moved amidst the dead, stripping armour and clothing off the bodies.

The door opened automatically as they approached, on the other side, a steep downgrade took them toward a brilliant light in the distance. "Where the hell are we, Shepard?" Wrex leaned back, hobbling a little as he shortened his strides to ease the passage down.

"I don't know." Shepard bit off a pained grunt with each lumbering step, so he slowed, trying to smooth his gait. "Not any part of the Citadel that I've ever seen." She took a deep breath, the air sounding wet and gurgling as it struggled in and out of her chest. Wrex may not know human anatomy, but he knew the sound of death when he heard it. His friend … his sister … had minutes to live.

"You okay, big fella?" she asked, leaning into his body a little harder, her arm clinging with a little less strength.

"Yeah, redundant systems and regeneration, remember?" He shifted his grip to hold her a little more securely as he crossed the narrow flat at the bottom of the strange, metal chasm, and looked up the other side. "You're the one who sounds like she's bleeding out inside." He nodded toward the climb. "Let's get this done."

Shepard coughed, wet and thick, a gob of bloody phlegm landing on the floor in front of them. "Better keep moving," she whispered, leaning in to rest her head against his armour. "Don't think you're far wrong on my bleeding out."

"Don't die on me, Shepard," he said, growling a little at the end. "I need you to work all the tech. Answering my messages and spending my credits pushes the limits of my tech skills."

He heard her smile in her sigh. "Don't worry, I'm not going anywhere until the Reapers die." Another cough, another splatter of blood on the floor.

They reached the top of the climb, stepping out onto a short walkway that led to a broad, round platform. A console stood on the far side. He might not know tech, but he knew enough to carry her across. To her credit, Shepard remained silent. That was one of the first things that drew him to her: the fact she never considered him stupid. She gave him a lot of credit, probably too much sometimes, but that had gained his respect and his trust.

Ahead of them, the lights of thousands of buildings still shone, millions of candles burning to mark the lives lived and lost on the massive station. He clenched his jaw and pushed on, keenly aware of the lack of the sounds that marked life amidst those of the great machine.

"Wrex." Shepard's voice seemed even tinier, weaker, less hers as it broke that eerie hum. "Set me down." Pushing herself upright, Shepard passed him the pistol and grabbed hold of the front plate of his armour.

He set her on her feet, then wrapped his arm around her to help her stand. Razor wire strands of pride, affection, rage, and grief sliced through his guts to wrap around his hearts, slowly slicing them into pieces as he watched her hands move over the interface. They didn't make lifeforms tougher and stronger than Jane Shepard even as her light began to dim, another candle about to be lit.

"I underestimated you, Shepard." The voice, male and smooth, came from behind.

Wrex leaned in close to Shepard's ear. "You all right on your own?" he whispered too softly to be heard by the enemy approaching on their six.

She nodded, the barest twitch of her head, as she continued working.

"I warned you," the voice continued, "control is the means to survival."

Wrex turned, scarcely registering the horror of the man's appearance—husk-like black skin and glowing circuitry erupting through broken flesh—before he charged. Dark tendrils of energy snaked through the air between them, but even as Wrex's body began to pull itself to a halt, impact. The wet crunch of bones breaking shattered the peace and the fist tightening around Wrex's brain released its grip.

Shepard chuckled, then let out a long groan and folded over the console. "Never monologue when there's a krogan in the room. That's lesson one." As Wrex returned to her side, she hit a final control, and with a series of bangs that shook the entire Citadel, the arms began to open. "Thank God," she sighed, crumpling to the floor. Kneeling next to her, he eased her up until she sat, her back pressed against him.

"Don't go anywhere just yet," he warned her, his hand gripped her shoulder. "We don't know if we're done here."

His radio crackled as the mission channel opened. "This is it, everyone, the arms are opening," Admiral Hackett's voice called out from the black. "Ten seconds to docking." Finding himself holding his breath, Wrex laughed, a rough, ironic rumble. He'd waited until the very last to let nerves take hold.

"That's it," Hackett continued, "the Crucible is docked."

"Did we do it?" Shepard asked. "Dear God, did we actually do it?" She slumped against him, her eyes closing, mouth hanging open as soft gasps panted between her lips. "I think I'm done, Wrex." She swallowed hard, tears cutting through the grime on her face. "Tell Garrus-"

"Shepard?" Hackett again. Shepard didn't move. "Commander?"

A small grunt acknowledged the admiral, but Shepard's eyes didn't open, and she showed no sign of actually having heard the call.

"They're not done with you, Shepard." Wrex eased her up. "They still need you. Wake up!"

She stirred at his bellow. "What do you need me to do?" she asked. Either some part of her had heard Hackett's call, or she'd just been programmed to assume every summons was a cry for help. Struggling, she tried to stand, but only managed to topple over onto her face.

"Nothing's happening," Hackett replied. "The Crucible's not firing. It's got to be something on your end."

Shepard pawed at the floor with one hand.

"Commander Shepard!"

Wrex heaved himself up then opened a channel to reply. "She's nearly dead, but don't worry, she'll save your pyjak asses, just like she always does." He lifted Shepard into his arms, cradling her gently so that she could see the controls. "They need you to activate the Crucible. What button is it?"

Head wobbling brokenly on her neck, she looked down, then reached out, fingers trembling. "I don't see … I don't know how to … ." Her head drooped, and her arms fell to dangle bonelessly from her shoulders.

Wrex laid her down on the floor and stood over her, trying to decipher the myriad of controls and gauges and readouts. "Shepard's unconscious, and I don't know how to work any of this."

"Wrex?"

The krogan's head snapped up. Garrus? "Vakarian, is that you?"

"I'm on my way to your position. Is Shepard alive?" The turian's voice came through strained and flat, clearly still injured and in pain, but strong and determined.

"She's alive, but not for long. They need us to make the Crucible fire, but I don't know what I'm doing. Get down here!" Relief flooded through him. Garrus would know what to do. The turian would be able to make it fire so that he and Shepard could finally rest.

"I'm nearly there. Hold on."

"Garrus?" Shepard's head moved a little. "Is that … ?" As she spoke, her voice carried as much doubt as wonder. "I sent you away on the Normandy."

"And I came back to get you." The turian sounded as though he was about to leap through the radio. "You hold on. You made me a promise, and I'm going to hold you to it."

The floor under Wrex's left foot began to move, lifting up into the air. For a half-second, he poised to pull it back, but it lifted Shepard up and away from him. Grumbling, he cursed himself under his breath and jumped up, crouching next to Shepard to make sure she didn't tumble off. She never moved under his hand, scarcely drawing breath.

The little raft floated up through the open ceiling, closing on a white light. It seared into his eyes, daggers stabbing into his skull. Wrex slammed his eyelids closed, his arm lifting to shield his face, and the pain eased. When the glare dimmed, and he opened his eyes again, they'd cleared the Citadel's structure. Space surrounded them on all sides, and he could see the battle going on around them. Ahead, at the end of a long platform of gleaming metal, a beam of energy roared from upward into the—

The krogan battlemaster stood and gaped, his mouth hanging open as he stared up at what must be the Crucible. Maybe the massive machine had brought them up to activate it. Movement drew his attention back to floor level, his mouth closing to swallow, then dropping open again as a small human child formed of glowing energy strode toward them, its steps quick and purposeful.

Wrex could remember few moments of true, stark terror in his life, but that alien place and its even more alien inhabitant scared him more than anything he could recall. And that included facing down the hologram of Sovereign as it told Vakarian, Shepard, and himself that their galaxy was completely screwed.

He crouched, one hand shaking Shepard's shoulder gently. "Shepard, wake up."

The commander stirred, lifting herself up onto a braced arm and coughed, blood splattering the sterile surface. "What, Wrex?" She looked around, her eyes squinting as if she couldn't focus. "Did the Crucible fire?" Looking up into his face, she blinked a couple of times, her eyelids sagging. "I thought I heard Garrus."

The glowing child stopped in front of them. It regarded Wrex for a moment, then appeared to dismiss him in favour of Shepard. Just as well, the thing made his tongue sweat and his plates itch.

"Wake up!" the child commanded and took a step back.

Shepard's head turned, reeling a little on her neck before she stopped to stare at the child. "Wrex?" she called softly, his name forming a question about both her sanity and living or dead status.

"It's real, Shepard. At least I think it's real." He stood and bent over to help her up, supporting her with an arm wrapped around her back when she managed to find her feet.

"Where are we?" she mumbled, turning a little to look out at the wreckage, the ships burning in space, the constant light show of beam weapons and explosions.

"The Citadel," the child answered. "It is my home. I am the Catalyst."

Wrex allowed Shepard to take a step forward, loosening his grip a little as she tested her legs, finding a strength he didn't think she'd possessed. If she could stand, he was more than willing to let her deal with the glowing kid and trying to fire the Crucible. Nothing in the half-millennia of his life had prepared Wrex for any of that madness. His place was shooting his way through the enemy, not handling the insanity of million-cycle-old AIs and creepy glowing children with voices straight out of the pits. That had been Shepard's job from the start, and she could keep it.

"The Catalyst?" Shepard asked, taking another step, pausing to buttress herself with a hand against her thigh as Wrex's support lessened. Her head hung for a moment before she forced it back up. "I thought the Citadel was the Catalyst."

"Wrex? Where are you?" Garrus's voice came through, badly broken with static. "I'm on the platform. You and Shepard aren't."

Half-listening to the Catalyst explain to Shepard that the Citadel was a part of it, Wrex backed off a couple of steps. "We're somewhere between the Citadel and the Crucible. Shepard's talking to the Catalyst. Can you find us?"

"Wrex, you're breaking up. Repeat. Where are you?"

The channel died, leaving Wrex no doubt as to what had cut them off. Turning to the Catalyst, he found the entity staring at him. The thing held the stare for a second, then turned and began to walk toward the energy beam.

"I need to stop the Reapers," Shepard said, limping after it. "I need to fire the Crucible. Do you know how?"

It glanced back but didn't stop. "Perhaps. I control the Reapers. They are my solution."

Wrex followed, staying close enough to Shepard to grab her if her strength gave out, but not so close as to include himself in their discussion. He didn't give two shits what the Reapers were or where they came from. He just cared that they needed to be blown into scrap. As he looked out over the battle, rage returned, smouldering under his plates. Why did Shepard spar with words, listening to the Catalyst's lies, allowing the Reapers to buy time? Surely she would never let it convince her to spare it?

It's explanations and excuses, it's logic—so flawed, even he saw the holes—didn't matter. What lie outside the glaring light, out in the black, the fire and death … the untold lives awaiting their righteous vengeance, the untold lives yet to be born only to face the horror of the harvest … those mattered. They were all that mattered, and they called out for one thing: the utter destruction of the Reapers.

And yet, Shepard listened. Barely able to stand, coughing her life's blood out onto the floor, she listened as it told her how to destroy them. Wrex crept closer as it continued, chilling his blood with its other options: controlling the Reapers or perverting every living thing into some bastardized form of machine life: part organic, part machine? Never! He hadn't stopped Saren from turning his people into puppets just to let Shepard do the same thing. He'd kill her before he allowed her to disgrace the billions who'd spilled their blood to end the Reapers.

"Why are you listening to this … thing, Shepard?" Wrex asked, his voice roaring in the near silence. "They couldn't force their synthesis solution on the galaxy, but now it'll work when you force it on us? You've fought for three cycles so the galaxy could choose its future, and now you're going to force us to accept becoming part machine?"

He stormed over to the child-creature, a thunderhead ripe with lightning ready to strike. "And control them? How do you trust that this thing won't just kill you while leaving the rest of us to be wiped out?" He slapped his pistol against her chest, nearly knocking her down. "There's one solution; the one we came here to see done. Destroy them and finish this."

Shepard grasped the gun against her, weaving slightly as she staggered, regaining her footing. "If I destroy the Reapers, I destroy EDI and the geth. And then the Morning War will come again in a generation or three or five."

"And you'll make peace again, like you did with the geth. Like you did between the turians and the krogan." He straightened, filling his chest so full of air that pain sliced him everywhere the armour had burned through his plating. "If the krogan had to sacrifice themselves to save the rest of the galaxy … if you asked us, we would. We are. Every species is out there, sacrificing themselves for the rest." Roaring his frustration, he gripped her shoulders, barely able to keep himself from throttling her. "None of us are guaranteed to survive this, but we're still fighting to kill these bastard machines."

He stared into her eyes, seeing nothing in the dull green orbs but exhaustion, pain, and confusion.

"It's begging for its life, Shepard. Don't listen." She had fallen past her ability to comprehend his words. "There is only one solution," he said, this time looking to the Catalyst. "And that is your destruction." He threw an arm out to encompass the Reapers still tearing their way through the fleets. "It's their destruction."

If Shepard didn't have enough left to make the right decision, he'd make sure she had only one option. He spun toward the energy beam and broke into a run, charging down the platform in case the Catalyst figured out what he intended to do and tried to stop him. At the last second, he turned along the path to the left, where the two conduits and their handles crackled with energy.

He winced away from the raw current, feeling the sheer power of it arcing over his hide even as he bent forward and charged, wrapping one arm around each of the small towers. Bellowing with the effort, he threw himself backwards, yanking at them with all his strength. A swarm of netichiks, the power from those conduits gnawed at his flesh, tearing him apart as it arced and sizzled along his body.

"No!" the Catalyst screamed, its voice losing the top layer of child-like innocence, howling like the evil it was. "You'll destroy everything. The Crucible is a power source! It will rip a hole in the universe."

Explosions shredded the platform, firing molten shrapnel into Wrex's face as he wrenched the conduits loose. "One decision. The most important decision in our history!" he roared over the maelstrom. Spinning, he charged back the way he came. "Destroy them, Shepard."

The commander, his sister in blood and now death, looked at the pistol in her hand, then nodded and took her first step toward the path to the right and the mechanisms she needed to destroy. Wrex's shouts transformed into one long, defiant bellow as he turned onto the main walkway, racing toward the massive beam of energy.

"One decision!" Ten metres or so away from the beam, he threw the conduits toward the searing pillar of light. "Only one! The most important decision—

Brilliant, blinding, burning, tearing light.

A light that felt like dying ...

Scorching, consuming, deafening heat.

… and then being born again.

"Wrex?" A strong hand thumped him in the back of the head hard enough to rattle his teeth together. "Wrex? Wake up. How can you sleep? We're late." The hand thumped him again, harder.

Wrex opened one eye and threw up a hand, shading his face against the light blazing in his face. Taking a deep breath, he scowled, his lungs filling with dry, dusty air that carried with it a thousand scents and flavours, including the odours of other krogan and roasting meat. The cold of space had transformed into a fiery, baking heat. He bolted upright, heaving himself up off broken stone and concrete, and spun, coming face to face with the sneering face of Wreav.

Scrambling backwards, he clambered the rest of the way to his feet, and turned a full circle, stumbling over rubble. "Where … ?" No, he knew where he was. He was home. Tuchanka. The Hollows. Where wasn't the question. Looking back at his dead brother, he reached out, gripping the other krogan's armour, the metal and ceramic solid in his hand. "What is going on here?" He dragged Wreav closer. "You're dead."

Wreav laughed, harsh and cold. "No, but if we keep Jerrod waiting, we all will be."

(A-N: This idea has been burning a hole in my brain for nearly a year. I told it to leave me alone, that I had other stories I needed to finish first, but it has been remarkably stubborn. So, here we have the first chapter of Stones Thrown Before the Tide. It's going to be a bear the likes of Future Non-Finite, but it will also be updated just as I get chapters sorted and down. Sassy and her boys are still my priority, but yeah … I can't resist the opportunity to completely mess with the timeline in a really massive way. I hope you enjoy the show.)