Hostage

The Avengers go after Thanos only to encounter a nasty surprise when arriving on his planet-
Loki didn't die that day on the ship of Asgard. Instead, Thanos took him captive and is now using him not only as a hostage, but also a means to destroy those who might attempt to reverse the affects of The Snap.

Thor was having a hard time believing what he was seeing.
After the crazy week he'd just had, you would think he'd be used to seeing unbelievable things by now.
He wasn't.

First, his father and mentor died. Next, it turned out he had a mad sister, (the Goddess of Death of all things!) and meeting him she had promptly shattered his hammer and later massacred half of his people in the name of securing the throne. He'd been forced to sacrifice his home (and his eye!) and then just as luck would have it, a crazed Titan had then shown up and decided to slaughter the remaining half of his people.
As if that wasn't enough, his brother had been (yet again) cruelly ripped from existence,
(but if he was perfectly honest he wasn't entirely sure that was true)
and Thor had been stranded in space, left to die.

A lovely start to his week.
It, unfortunately, only got worse from there.

One wild adventure later where he faced all the force of a burning star, met a talking rabbit, and destroyed a whole army of gruesome beasts before finally plunging his axe into the titan's chest, he finally thought he had slain the purple beast that had massacred his people.
He was horribly wrong.

Time seemed to slow as Thanos snapped his fingers… Then the whole universe shifted and Thor was left staring at the smoking, shattered gauntlet, begging the Norns to let his eyes be lying.
To let this be a cruel trick, or perhaps let the gauntlet have finally have broken, unable to channel the might of all the stones and unable to perform its master's last request.
(He knew it wasn't.)
The god had felt the very nature of reality change, felt the delicate balance between life and death be decimated in an instant…
And yet the only words he could manage, a faint whisper on the breeze formed a question he already knew the answer to.
"What have you done?"

And now? Right now, in this particular moment in time?
After those remaining had regrouped, after he was forced by his own guilt to look them in the eyes and admit that his hunger for revenge had blinded him- that this cruel fate that had befallen them was all his fault…?
(For he felt in his heart that it was, no matter what the Captain tried to tell him)

After they had broken into the 'new' Avengers building and Rhodey had lead them to Tony's workshop, shown them the things Tony had made for them before and after their 'break-up' and the truth of Siberia had finally emerged..?
(Rhodey stood, expression completely blank as Steve finished recounting the story- the true story of Siberia. Of how the fight had broken out and he had lied and Tony had snapped and Bucky- Well, Bucky had ran. And then Steve snapped too and all he could feel was the need to protect Bucky, to protect all he had left.
And that Tony,
Well,
Tony had gotten in the way.
And Tony was left in the snow.)

After Rhodey had stepped forward and Steve back, arms flying up to defend himself and Rhodey had just shook his head, disappointed-
Had told them of how Tony had stumbled home with severe blood loss, pneumonia, and had told them that he'd fucked up, that he'd hurt Steve and Bucky and told a very different story of Siberia-
"I'm telling you, Rhodes, it's not his fault. He told me about my parents ages ago and when I turned up he was thrilled. Greeted me with open arms. Bucky was alright too I guess- not quite the person I imagined but then again, neither was Steve. Who am I kidding, he's the walking definition of Patriotism. You know what I mean. Anyways. All that just made it even worse when that asshole turned up- the guy who was causing all that shit to go down before, the attacks- and I just kinda lost it. I went absolutely ham on Bucky and then Steve tried to talk me out of it but I just kept going. Nearly killed them both- I was lucky he knocked me out in time and still dropped me off by the Avengers tower. I owe that man my life, Rhodes, and all I've ever done is bring him pain."

Steve's eyes glittered and Nat pulled him into a hug, hands falling hesitantly on his back even as he sobbed into her shoulder, the stress and the fear of the fast few days finally sinking in.
We are losing, we have lost, we are breaking, we have broken-
When Rhodey brings out Cap's shield, polished and painted to perfection by Tony, all six bullet scrapes gleaming in the light Steve tries to make him take it back-
He didn't want the thing before, didn't need it when he had Bucky. But now, with no Bucky to make him Steve and no Tony to make him Cap, who is he?
Rhodey shoves it roughly into his arms anyway. His face offers no chance for discussion.
"He wanted you to have it."
And that's that.

After that it was just a whirlwind of trying on new gear, of shrugging on shoulder plates and tossing knives in their palms.
He knew of another who loved knives. Thor wondered if a shard of Loki's knife had broken off in his chest and never emerged for every time he thought of him, his heart ached.
Grief was cruel like that.

They eventually emerged from the broken building, stepping through empty window frames, boots crunching on shattered glass.
The king of Asgard lifted his hammer and light split the sky. Strands of pink, yellow, green and blue gleamed and the bifrost flickered into being.
Their plan was simple; no one was in the mood for talking.
Go in, take out Thanos, reverse the Snap.

Of course, it was never going to be as simple as that.

He was broken.
And yet somehow, as if the tiny shards weren't quite small enough, someone was trying to break him further.

Thor's world was crumbling, shattering and spinning out of control with terrifying speed.
It was a feeling not unlike drifting dangerously close to the edge of the bifrost, a raking of glorious, painfully sharp crystals down your spine; a thrill of exhilaration as you glimpse the void, as phantom winds batter you back and forth, as you see darkness, light and the end of all things.
He had felt this feeling only twice before.

The thunder god's breath caught in his throat.
His hand gripped the axe so tight his knuckles went bone white.
His forehead was furrowed nearly to the point of pain and he was frozen, staring with horror and disbelief, not daring to believe what he was seeing.
For in Thanos' cruel grip was his brother
Loki.
Alive.
Again.

"Hello, brother." Loki managed, face already twisted into a apologetic grimace.
"Loki." Thor choked out.

The Mad Titan grinned.