Gwen, Rhodey, Pietro, Bruce, and Rocket were stuck under the rubble as water came flooding down to where they were.

Bruce was using his one good arm to hold up the rubble.

Rocket had a heavy piece of rubble on top of him.

Pietro's left leg was bent in a way that it shouldn't be bent. His speed-healing was working, but it wasn't going fast enough.

Gwen was using her enhanced strength to hold up another piece of rubble from crushing Pietro.

Rocket: I can't breathe! I can't breathe! I can't breathe!

Rhodey: Canopy! Canopy! Canopy!

Rhodey's War Machine suit opened as he crawled out of it and towards Rocket.

Bruce: Rhodey, Rocket, Gwen, Pietro, get out of here!

Gwen: I can't! Not without getting Pietro killed!

Rhodey was crawling towards Rocket.

Rocket: Hurry up!

Rhodey grabbed a rebar and used it as leverage to lift the heavy rock from Rocket.

Rocket managed to get out as he and Rhodey lied down panting.

Bruce: RHODEY!

Suddenly, a large wave of water came flooding into the room.

Meanwhile

Scott had managed to shrink before the explosion hit him.

He dug himself out of the rubble when he heard Bruce's distorted voice on his comms.

Bruce: (on comms) Mayday, mayday! Does anybody copy? We're on the lower level, and it's flooding!

Scott: W-What?

Bruce: (on comms) WE'RE DROWNING! DOES ANYBODY COPY? MAYDAY!

Scott: (into his comms) Wait! I'm here! I'm here, do you hear me?!

Meanwhile

Aaron had been knocked out by the blast.

???: Aaron, get up.

Aaron slowly opened his eyes and saw Tony and Steve standing over him.

Tony: There we go.

Aaron: The hell was that?

Steve: We don't know, come on.

He pulls Aaron to his feet as the three walk towards Thor, who was looking at something outside.

They looked at what he saw and they were shocked to see it.

It was Thanos, alive and well, sitting there. He had his full armor on and a double-bladed sword next to him.

There was only one explanation that this was possible.

This Thanos is from the past.

Tony: (to Thor) What's he been doing?

Thor: Absolutely nothing.

Steve: Where are the Stones?

Aaron: Somewhere under all the rubble, I think. One thing's for sure, he doesn't have them yet.

Steve: So we keep it that way.

Thor: You know it's a trap, right?

Aaron: I'm aware. Don't really have a fuck to give, though.

Tony: Neither do I.

Thor: Good. Just as long as we are all in agreement...

A thunderstorm formed at Thor stretched both his arms outward. His armor formed around him as both Mjölnir and Stormbreaker flew into his hand.

Thor: Let's kill him properly this time.

The four approached Thanos as he noticed them coming.

(A/N: Aaron is with them, wearing his Flash suit)

Thanos: You could not live with your own failure. Where did that bring you? Back to me.

The 4 Avengers circled Thanos as he continued.

Thanos: I thought that by eliminating half of life, the other half will thrive. But you've shown me...that's impossible. As long as there are those who remember what was, there will always be those that are unable to accept what can be...They will resist.

Tony: Yep, we're all kinds of stubborn.

Thanos: I'm thankful. Because now... I know what I must do...

He gets up.

Thanos: I will shred this universe down to its last atom. And then, with the Stones you've collected for me...

He puts on his helmet.

Thanos: Create a new one. Teeming with life.

He picks up his double-bladed sword.

Thanos: That knows not what it has lost, but only what what it has been given.

Thor charged up his hammer and axe, while Aaron produced orange sparks out of his body.

(A/N: Like this)

Thanos: A grateful universe.

Steve: Born out of blood.

Thanos: They'll never know it...Because you won't be alive to tell them.

Thor lets out a war cry as the four attacked Thanos at the same time, but he in managing to either block, evade, and counter all of their attacks.

Meanwhile

The room was almost full of water.

Gwen was holding Pietro, whose leg still wasn't fully healed, to make sure he doesn't drown.

Pietro: (to Gwen) Gwen, just let me go. I'm dead weight right now.

Gwen: The hell you are.

Scott: (on comms) Hang on! I'm coming!

Meanwhile

Tony had made several repulsors protrude from his back, along with a charging point.

Tony: Okay, Thor, hit me!

Thor had summoned lighting and shot it at the charging point, allowing Tony to create more repulsor shots at Thanos, who blocked it.

Thor tossed Mjölnir into the air and swung at it like a baseball at Thanos. Unfortunately, Thanos picked Tony up and used him as a shield and made him take the hit instead, knocking Tony out.

Aaron had speeding around, landing as many punches and kicks as possible at Thanos. But Thanos noticed a pattern in Aaron's attacks and predicted his next move.

he had grabbed Aaron and dropped him back-first into his knee, breaking his spine, before tossing him aside like a ragdoll.

(A/N: Like this)

Good thing Aaron's speed-healing was working, but as of now, he was immobile.

Thor swung his axe, at Thanos, but he blocked it with his sword before disarming the god and throwing him into a rock.

He was pummeling Thor as the god tried calling for Stormbreaker, but Thanos grabs it and pushes it towards Thor's chest. Thor was pushing back, but Thanos was slowly gaining the upper hand.

Suddenly, Mjölnir flew in and hit Thanos before flying back...towards Steve.

Thor: (smiles) I knew it!

Thanos knocks Thor out with a kick before turning to face Steve.

Thanos and Steve charged at each other as Steve used both the shield and Mjölnir to attack Thanos.

Steve then threw lightning at Thanos, sending him back before summoning lightning from the sky and dropping it at Thanos.

Steve went for another attack, but Thanos dodged before slamming Steve into the ground.

He picked up his sword and swung it at Steve. He slashed Steve's leg before knocking Mjölnir off his hand.

Thanos went for an overhead swing. Steve blocked it with his shield...But the sword broke through the vibranium shield.

Thanos swung at the shield repeatedly until it was broken in half.

With one powerful swing, he sent Steve flying until he landed next to Aaron, whose spine healed, but he was in no shape to run yet.

Aaron saw the state of the shield and was shocked. What the hell was that sword made of that it was break through vibranium?

Thanos: In all my years of conquest, violence, slaughter...it was never personal. But I'll tell you know...what I'm about to do to your stubborn, annoying little planet...I'm gonna enjoy it...Very, very much.

That's when his army came down to Earth, and it truly was the biggest army in the universe.

The Black Order, Chitauri, Outriders, Sakaarans, and other creatures that were too many to count.

Aaron and Steve looked at the army in front of them, then at each other. They knew they couldn't take them on alone, but they were not going down without a fight.

They both got up as Steve tightened the straps to his broken shield. They both walked up to the massive army before them, fully intent to taking as many as they could down with them.

???: (on comms) Cap, Flash, do you read me?

Aaron and Steve stopped in their tracks as they both heard a voice they haven't heard in a long time.

Sam: (on comms) Cap, Flash, it's Sam, do you hear me?

They couldn't believe what they were hearing.

Sam: (on comms) On your left.

[There should be a GIF or video here. Update the app now to see it.]

(A/N: I'm sorry, this scene simply can't work without this work of art)

The two turn to their left and saw a portal open as three figures emerge from it.

As they got closer, Steve and Aaron recognized the figures.

It was T'Challa, Shuri, and Okoye.

Steve and Aaron looked at the three in disbelief as Sam flew out of the portal and turned to their left.

They then see multiple portals opening with multiple beings emerging from them.

From one portal emerged Doctor Stephen Strange, Drax, Mantis, Peter Quill aka Star-Lord, and Peter Parker aka Spider-Man.

Aaron smiled at the sight before him.

T'Challa: YIBAMBE!

Wakandans: YIBAMBE!

More people from across the galaxy emerge from the portals, but one person stood out for Aaron.

It was Bobbi Morse, in her Mockingbird suit.

From the other portals emerged Bucky Barnes, Groot, Valkyrie (in her Pegasus) Wanda Maximoff, Korg, Hope van Dyne aka Wasp. Along came Wong and all of the sorcerers, Ravagers, Asgardians, and Lord knows how many others species.

But the real surprise for Aaron was seeing Jimmy de Luca in what looks like a makeshift Iron Man suit of his own.

Just then, Pepper Potts, in a suit of armor like Tony, landed next to Jimmy.

Strange: (to Wong) Is that everyone?

Wong: What, you wanted more?!

Just then, Scott Lang, enlarged, emerged from the rubble. He opened his hand as Bruce Banner, Gwen Stacy-de Luca aka Ghost Spider, James "Rhodey" Rhodes aka War Machine in a new suit, Rocket Raccoon, and Pietro Maximoff aka Quicksilver (fully healed) jumped out of it.

Aaron smirked as he and Steve stare Thanos down with an army of their down.

Aaron: (to Steve) Call it, Captain.

Steve nods before taking a few steps forward.

Steve: AVENGERS...!

He summoned Mjölnir to his hand.

Steve: Assemble.

(A/N: YEEEESSSSSS!!!)

Both sides charged at each other at full speed.

Eventually, the two sides clash...

The Battle of Earth has begun.

(A/N: Stop the music at 2:28)