Also, I forgot to plug this last time, but: this is actually the first of TWO Christmas-present fics I am writing this year. the other is my third-annual collab with EnduranceinHope, back on her profile this year. It's called 'Peace on Middle Earth' and is a series of vaguely Christmas-themed LOTR one-shots updated daily until Christmas Eve. Head over to her page and check it out!

Hello, everybody; ModernDayBard here!
Here we are with the penultimate chapter: the big battle against Thanos! …That was an intimidating thought, to say the least, but ultimately, I liked how it turned out. Hopefully, you will, as well!
Disclaimer: I don't own Marvel, their characters, settings, McGuffins, etc. I own the ideas I suppose, as much as anyone can (though they've been heavily influenced by listening to discussions and reading other fics) and the words that I have chosen to narrate with.

There'd been some discussion about formations and tactics—since Thor's ax should be able to transport them right to the first planetoid they thought Thanos was on (albeit not instantaneously, even the Bifrost would have to take nearly a minute to cross the universe), they'd arrive in the same positions as when they left, so they had at least a moment to consider it.

The discussion had been complicated by one final arrival the night before: a woman calling herself Captain Marvel, who'd gotten a long-distance summons from Nick Fury himself before he disappeared. Combining her space-traveling experience with what Nebula had already told them, they were able to narrow three options down to two for finding Thanos, and adding her not-inconsiderable power to their strike force was a last-minute morale boost, at the very least.

Finally, some semblance of order had been reached, with a sense of 'ranged fighters here, close range here, those that can do both here,' but loosely, as where Thanos would be and what resistance he would or could muster in the first few minutes of the attack (when they threw everything they had at him in hopes to take him down and out before he could counter), were unknown factors at that moment.

Peter found himself standing with Nebula on one side of him, Clint on the other with Natasha standing beside the archer. They weren't that far from the front, where Col. Rhodes, Captain America, Bruce Banner, M'Baku, Okoye, and Captain Marvel stood around Thor, who had Rocket perched on one shoulder and raised his ax skyward with the other arm.

Impossible colors surrounded them, there was the sensation of movement—or rather, that everything around him was moving while he was standing still, and, for a moment that stretched to a minute, Peter found it hard to breathe.

There had been some attempt by those who'd traveled via Bifrost before (which was to say, Bruce, Thor and Rocket) to warn the others what the sensation was like, but words failed to capture the disorienting power of the innocuously-named 'Rainbow Bridge'.

As abruptly as it began, it was over, and those that recovered first could see just over the rise they'd landed on was a single small hut with a too-familiar, imposing figure in front of it, standing still and staring at the pitiable excuse of an army that had just landed on his doorstep, pissed off and ready to show him just how 'grateful' the universe truly was.

With a single roar from every throat, every Avenger leapt forward into battle—the final battle.

For the element of surprise to guarantee success, you had to get your target from behind, Natasha decided. They had caught Thanos off-guard, at least at first, but he recovered far too quickly for their initial assault to secure victory immediately.

The one thing keeping them alive was that, as Thor had said, the Gauntlet seemed to have sustained massive damage from the Snap, and after using it a single time, Thanos relied on his own not-inconsiderable strength to fight back the assembled heroes that got close.

However, that single use had been to use the blue stone—the Space Stone, Thor had called it—to open a portal and summon the fragment of his army that remained to battle on his behalf. They were different species, and their numbers nowhere near what they'd been in Wakanda, but each still fought with the same mindless determination that was only ended in death, making it a slog to get anywhere near the Mad Titan, much less fight him.

It almost became mechanical, after a point, but the one time Natasha let herself scan the field, she paid for it. Before she could locate anyone in the chaotic frenzy, she was hit from behind with some sort of electrical weapon blast and fell still alive and fully awake, but (hopefully) temporarily paralyzed.

Nat was down.

The thought crossed his mind in a moment, and the archer halted his reckless forward charge to stand by the closest thing to family he had left, keeping the horde off of her until she could recover—if she would. No, no time to think about that—only fight.

As much as he could, Clint was using his bow as a two-handed, close range weapon, having learned too often that, no matter how many arrows he brought, it was ultimately a limited supply. After all, this looked to be turning into a long fight. Every now and again, if there was a lull around him and he spotted someone in trouble further away, he'd loose a single arrow to their aid—and not for the first time, the incongruous, fanciful thought crossed his mind that, if he were an archer in a movie, he wouldn't run out of arrows ever, until or unless the plot demanded he did.

Ammunition gripes aside, he continued splitting his focus between his own immediate vicinity, and the half-dozen other fights strung out across the field between him and Thanos' own battle (who with even Hawkeye couldn't tell). He saw the blue-space-cyborg girl a ways down the hill, fighting two monsters while a third charged in from the side, and Clint nocked an arrow, taking aim on the easy target.

As he prepared to fire, he realized he, too, was being charged at from the side. He released the shot before turning and firing at the other comer, but while his foe was dead, its momentum remained unchecked, and the behemoth crashed into him, bulling him to the ground and pinning him under what felt like a half-ton of alien carcass.

Nebula didn't see where the arrow came from, and didn't particularly care, but she did appreciate where it went: right into the eye of the creature about turn her current fight from difficult to impossible.

Her twin swords were still flashing, despite the sheen of various shades of blood coating them. She was still nowhere near her father, and a frustrated scream tore from her throat at the enemy-choked field between her and the true target of her rage.

Releasing what tenuous grasp on sanity she had, she dispatched the two she was still fighting and began her head-long charge again, cutting down any of Thanos' army that dared stand in her path, not caring for the many wounds she accumulated as she roared and charged.

Without realizing, her wordless scream had taken form, form as the only word that mattered to her at the moment repeated over and over as her technological and organic parts were sliced, torn, and bitten by the hoard that now completely surrounded her: "GAMORA!"

Her forward progress was checked again, but her swords kept dancing, and she kept screaming.

"GAMORA!"

With a snap, one of her metal legs gave, and she was down on one knee, but she kept fighting.

"GAMORA!"

Fangs sank into her left shoulder, deadening that arm, but she killed that creature, and one just behind it.

"GAMORA!"

Something hit her from behind and she fell forward, final cry muffled by the dirt that filled her mouth, but just as she lost consciousness, another voice took it up and added to it as the sound of a weapon firing continuously filled the background.

"GAMORA! QUILL! MANTIS! DRAX! GROOT! THEY WERE MY IDIOTS, YOU BASTARD! I'M GONNA KILL YOU!"

All the Guardians were crazy—anyone who met them, let alone worked with them for a single mission, even—could tell you that. Each occupant of that ship had their own approach to, claim on, and flavor of insanity, but the bizarre mix of personalities on the team ensured that, when one got out of hand, or took a swan dive off the cliff of relative sanity that particular individual dwelt on, the others would be there to pull them back, keep them in check, or, at the very least, run damage control.

But not anymore.

Now Rocket was the only one left, with no one left to pull him back, and no real reason to even want anyone to. He was a two-foot tall, silver-furred, curse-spewing demon of death, and no one on that planetoid could keep pace with him, much less keep him under control.

His small size helped him evade many of the larger aliens Thanos had summoned to fight back the Avengers and their allies, but as he was not actively even thinking about dodging, it was only a matter of time before a stray kick, then a back-handed swing disarmed him and sent him flying into a bolder, doing what none of the other heroes remaining could: stopping the damn raccoon.

Rhodey was a part of the aerial-support squad.

No, he was the aerial-support squad.

Without the Falcon, Vison, or Stark, he was the only hero remaining who fought predominantly from the air, thus it fell to him to lay down cover fire, read the enemy's pattern from a bird's-eye view, and quickly get to the other fighters who needed him most. Just when he thought there wasn't a way to miss the fallen any more, tactics and logistics had to go and prove him wrong.

Still, there was no time for grief or regret, there was a job to do, and now he was the only one there to do it.

As his view and approach was, by necessity, wider and more general, he couldn't afford to seek out particular allies to aid or protect, so as much as some instinct told him to keep an eye on the kid, he knew he couldn't do it—Tony had trusted Peter enough to invite him to be a part of the Avengers once before, now Rhodey had to trust his friend's judgment and the kid's skills to keep Spiderman in one piece while they each did their part.

He couldn't be everywhere at once—and it was beginning to tell. One by one, they were falling, though the army was being decimated as well. At the rate they were going, they would defeat the hoard, but there wouldn't be anyone left to fight Thanos afterwards. They were losing.

Almost as the thought crossed his mind, a stray shot from below—one knocked astray, not even aimed at him—hit the suit, and the too-familiar sensation of falling heralded the end of any air support for that battle.

He was still conscious upon landing, the improved suit having taken most of the impact, but before he could regain his feet and rejoin the battle, he was dog-piled by several of the remaining aliens, tearing and biting at the metal in an attempt to get to him.

Carol Danvers was new to the group, true, but she was hardly new to fighting, or to her powers, though Thanos had never crossed her path.

He was coming to regret doing it now.

Captain Marvel and Thor had been the first two to make it to the Mad Titan, with Bruce (still in the Hulk Buster suit) and Captain America just behind them. Still, Thanos was holding his own. Four-on-one had been a bit much without use of the Gauntlet, but a pack of wolf-like beasts the size of tigers had leapt on the metal behemoth that housed Bruce Banner and started shredding it, forcing Thor to go to the aid of the scientist, and leaving the two Captains to tag-team against the Titan.

Still, the purple bastard was remarkably resilient, if desperate, and while Carol and Steve could hold him back, without something to tip the balance, they couldn't take him down on their own.

Before they could decide what that was, they found out just how desperate Thanos was, as he used the Gauntlet for only the second time since the battle began: calling forth a purple blast from the Power Stone that knocked her several yards back, winded and disoriented, leaving Captain Rogers facing the giant on his own.

Steve had a half-second to register that Captain Marvel had been knocked away and was not immediately getting up, and probably less to note the sounds of protesting metal and wordless roars behind him—Thor still hadn't gotten all of the aliens off of Bruce, it seemed.

No one else was close enough to lend any aid, it was just him against the Titan who'd killed half the universe. Steve didn't really think he could beat him after their last encounter in Wakanda, but he'd be damned if he didn't at least try. Thor was still up and fighting, and from the corner of his eye, Steve could see Carol stir. He just had to buy time for more heavy hitters to join the fight.

He only just noted or thought any of that, when a giant purple fist slammed into his side, and with a 'crack' something gave that felt suspiciously like bone. Before he could recover, the Gauntleted hand caught him a back-handed blow that knocked him several yards away, leaving the Titan unencumbered for the first time since the battle began.

Bruce had never been what anyone would call 'fond' of the Hulk, even after the events of New York, the first time he'd turned and not been immediately rejected. There'd been an understanding after that point, he'd felt, but still he hated to relinquish control, and after the Scarlet-Witch induced rampage, they'd fallen completely out, leading to the longest two years of his life, if he'd been aware of them.

Things had spiraled pretty quickly after that, landing the two back into the power struggle from the Hulk's first days, and then this—

In the strangest reversal the scientist had ever faced, he wanted the Hulk to come, and he would not. Even now, under the weight of who knew how many enemies, with the Hulk Buster suit threatening to crush or trap him, there wasn't even an echo of the giant green monster who would've been really helpful right now!

Part of the helmet was ripped away, which was terrifying, but gave him his first real view of the fight in several minutes, just in time to see both Captains go down and Thor glance over at the now opponent-less Thanos. Bruce looked around, saw they were down to three aliens themselves and yelled to Thor: "I got it from here—go!"

The Asgardian hesitated a second, but the sight of Thanos striding towards the nearest knot of fighters, fist raised, decided him.

Now alone, in a half-destroyed suit and with no chance of backup from the Hulk, Bruce turned his attention to the three beasts still clawing their way through the armor, mind racing to come up with even the shred of a plan.

Thor heard the sound he'd long ago come to associate with Stark's weaponry firing behind him, though louder and more sustained than the inventor's precise, strategic blasts, and could only hope that Banner had truly found a way to extricate himself—or at least, defend himself.

As much as it cut him to the core to leave one more person behind—risk losing even one person more—he knew he had only one chance to end this.

As Thor ran, he restrained the battle cry that was desperate to tear forth, concentrating on the Titan whose back was to him, and hearing a too-familiar voice in his mind, speaking with half-feigned exasperation.

"Subtlety is entirely lost on you, brother, but do consider for a moment that, should you actually ever try to catch a foe off-guard, some measure of care should be taken not holler, 'I am coming for you' at the very top of your lungs."

The words were from a happier time, but all his mind's-eye saw was a struggling form in the Titan's grasp that he hadn't been able to save.

He heeded the warning, held his tongue, and swung his axe forward—going for the head this time—

And Thanos turned, catching it with a twisted smirk. "No second chances."

Repeated blows, no chance to counter and then—the sensation of flying, so different from being under his own power.

I'm sorry, Loki. You always were better at surprise attacks.

Thanos stood still, surveying the once-empty field, now littered with the corpses of his army and the dead, unconscious, or otherwise-immobilized forms of the group that had dared to attack him.

A rumble of disappointment or anger started in his chest—even now, were there those that didn't understand what he'd been aiming for: what he had accomplished?

"This was a pointless attack," he said at last, unable to stop himself, even if there were none to hear or heed him. "The battle was over—all you had to do was go home and enjoy life in the universe I gave to you. Don't you understand that I saved you? No more fights, no more problems. Can you not see—"

"No."

He hadn't been expecting a response, and turned to see one of the fallen forms stand—ah, yes. The small one from Titan. The one he had spared. The boy had come back, even knowing he could die—that he would?

Peter stood, albeit unsteadily after some of the hits he had taken, and he wasn't sure exactly why he was talking instead of fighting, but something about the smug way that Thanos was talking about 'saving' and 'enjoying life' just sickened him. "I don't understand." He wished he sounded more like an awesome hero and less like a terrified kid, but Thanos had stopped and was staring at him, which was as close to an invitation to lay into him as Peter was going to get, so he did what some claimed Spiderman did best: he talked.

"I don't understand," he repeated. "I don't understand why you really did all this. It wasn't to save the universe or anything like that. If the universe really was running out of resources, and if that Gauntlet really is all-powerful, wouldn't it have been easier to just double the number of resources? Or re-distribute them so everyone has enough? Because killing people just makes it worse—the infrastructure needed to get the resources to the survivors have been decimated, and people are still dying and you haven't saved a single damn person, and anyone who even thought of this plan for a single second would've known this was how it would turn out, so if you still went through with it, you couldn't have actually wanted to save anyone!

"So, I don't understand what you were actually trying to get—was it power? But no, you came out here to a god-forsaken, glorified asteroid instead of ruling anything, so it wasn't for a throne at least. The only thing I can think of was that you just wanted to kill people. And I don't understand. I'll never understand that. I'll never understand what kind of sick bastard gets satisfaction from knowing they now have the highest kill count in the history of the universe, or from the suffering of the survivors. And I'll certainly never understand who does all that, and then demands gratitude from the people he didn't kill.

"I. Don't. Understand."

Thanos stared at the boy, stopped in his tracks, blind and deaf to all else around him. Of course, the child was too young to understand—surely he was just flailing out blindly in the dark—he, Thanos, had often wrestled with this conundrum in his mind, and every time, came to the same conclusion: this was the right thing to do because…because…because it was right, and he knew it was right! He wasn't cruel, he was merciful. He didn't kill, he spared. He wasn't a monster, he was…he was a god!

How dare this mere infant, this insignificant speck question him, and dare tell him that this was for power or pleasure? Just because he did, eventually, enjoy it, surely that wasn't the reason—no, of course it wasn't. To save the universe, he had to eliminate half the population, it was simple math. It was what had to be done, and he was the only one who could see that, much less do that—

Heedless of the Titan's crises of identity and faith, three individuals hauled themselves up first, even as many more across the field began to stir in the lull they'd been granted by Peter's distraction.

Steve Rogers hurled his shield (a hasty recreation Shuri had whipped up in between battles, but nearly indistinguishable from the original) into Thanos' left shoulder, damaging the un-Gauntleted arm, Carol Danvers fired a blast from where she stood, focusing on the Gauntlet itself and shattering the already-weakened metal, and Thor dove in, axe in hand—

And finally, finally, hit the head he aimed for.

Later, when they had time to think about it, several Avengers grumbled that it had been anti-climactic how Thanos had dropped, dead, after the hit from Storm-Breaker, but that was in the quiet, restored hours when desperation and terror had given way to only half-meant mutterings.

The more immediate concern, in that instant, was the fact that the Infinity Gauntlet had been destroyed, but the Stones had not, and they tumbled loosely over the ground, freed from their housings. Those who were close by—or had worked their way close during Peter's speech—lunged for them instinctively, knowing that, if the stones were lost, ultimately, so was the universe, still.

Steve was the closest, and the blue stone that, in another life time, had cost the soldier so much seemed to bounce straight into his hand. The familiar red stone, so different in this form, now, came to rest in Thor's grasp as he dove for it, while Bruce pulled himself out of the ruined suit just in time to catch the purple stone that he'd seen in action on the refugee ship.

Clint didn't recognize the yellow stone he scooped up at first, but he recognized the feel of it—Like an echo of one of Vision's blast, or the searing un-making of the scepter, and he held it tighter against the urge to fling it away. Nat had no idea of the significance of the orange stone she grabbed, or what it normally cost to hold such a power—but then, hadn't everyone lost someone in this reality that shouldn't have been?

The green stone fell to Peter, who seized it without thinking, really, of what was coming next. Instead, he remembered a different alien world, and what had been lost or traded for the tiny scrap he now held in his hand.

Six Stones—six powers—six parts of a whole nearly too terrible and too strong to comprehend—and six bearers, seemingly random, simply in the right place and time. Yet each, though they could never afterwards put into words, felt that they had been pulled or drawn to 'their' stone, and the way the purportedly non-sentient stones bounced or rolled seemed to indicate that they, too, had been tugged in those directions, towards those Avengers. Six stones—six bearers—six hands closing in the same instant.

A shock rolled over the fields, stunning the other heroes only just pulling themselves up, and pulling the six away from all awareness of anything but the Stones, their power, and the others holding a part of Infinity.

All that could be felt was overwhelming power, even identity faded, for a second, in the all-erasing energy of the Six, but the same desire in six hearts—to set all to right—tipped the scales back into tenuous balance, and six connected but unique Minds and Souls reached for the Power to bend Space and Time in order to return Reality to what it should be.

At first, it seemed to work, the great energy gathered, preparing to surge outward in response to the force of will applied to it, but then—

Toll.

The knowledge was almost a voice—an insistence they neither felt or head, but knew all the same: for every use of this concord, to use all Six at once as One, there was a cost. The Orange stone flickered greedily, its tendrils flickering against all six, seeking its satisfaction before the storm could be unleashed—the universe would be bought with one more life, or the building storm would destroy the broken fragments that remained.

Spare the boy, and I will give you what you want…It had to be this way.

Had to be this way…had to be this way...spare the boy...had to be this way…

Of course—that was it, wasn't it? The whole reason he'd survived was so that he could keep the promise he lived to make to Ned, May, and MJ—that he'd bring back the half of the universe that'd been stolen away. That was what Strange had seen in the one time they won, wasn't it? This was why he'd known this was where he had to be, what he had to do—

No.

It wasn't the voice of Infinity, but it held as much authority and insistence.

Not him—me.

If Peter was still receiving any sensations from his eyes, they'd have fixed on Captain America, wide with surprise. As it was, the shock he felt rippled through the other four—and the Six as well.

The world has more than enough defenders, now—

Who or what was being addressed was unclear, but somehow, in this blending, this confusing not-reality that was all that existed, all five others knew what the other part of their whole was getting at.

—it needs rebuilders.

Orange tendrils reached out, grew thicker, flared, then six was five and the power couldn't be held back, controlled, or even directed: it burst forth, touching every point in existence at once, searing burning, destroying—

Undoing.

So, yeah.
The battle was kinda fun to write, to be honest. I knew trying to give a wide perspective of everything going on and the general tide of battle would've left it flat, so I chose to zoom in on little vignettes centered around characters and their emotional state as much as their strategic positioning. I'm not usually a visual writer (in that I don't have a clear picture in my mind's-eye of the scene as I'm writing it), but I could almost see the battle play out like a faux long-take in a film: the camera would pan down as Natasha fell, Clint would step into frame. We'd track the arrow he fired and let it pull the camera to Nebula and her fight, then Rocket would run by, etc. I really liked the end result of that.
Then there was the 'I don't understand' moment. That one I borrowed/plagiarized…from myself. I tend to play through a lot of oc-insert plot bunnies, etc., just in my mind—particularly after the first time I watch a movie/tv show. One of my post-Infinity War plot bunnies saw one of my oc's in this sort of battle, in this situation, giving a rant similar to that, which had the same effect: slow Thanos down enough for everyone else to get up. Of course, Peter had to have a moment like that in my mind, since that was why (in my mind), Strange knew he had to live. The Avengers would've lost then and there is someone didn't stop Thanos in his tracks and distract him, and it's been shown Thanos can be distracted...by kids (Gamora flashback?). Also, it gave me a chance to get in all the not-so-little points I've seen people go over about how Thanos' plan kinda stinks and his motivation doesn't make any sense. I subscribe to the theory that he lied to himself for so long, he came to believe it.
And finally, the Infinity Stone scene. For this one, it was the opposite of the battle—I wasn't capturing a mental visual, but the feeling of the utter power and confusion of the Stones: I took a lot of inspiration from Guardians 1 and the scene with them holding the Power Stone. And like I said in the first chapter—I don't believe this is how the movies will fix it. This is just how I decided to have this play out. Anyhow—one more chapter to go!
As always, if you saw something you liked, or something you think I can fix/improve on for next time, don't hesitate to leave a review and let me know!