Author's Note: Here's the first chapter to the start of a crossover I was wanting to write for a long time coming! This is set in the Avengers Assemble series and TMNT 2k3 series. Two of my favorite shows, put together! I hope you enjoy reading.

This is most likely going to be exclusive to this site only, no cross-posting to my AO3 account.

Disclaimer! - I do NOT own TMNT or any of the MCU characters. The only thing I own is Lydia Moon Barnes, my OC.


Brock Rumlow walked through the halls of the base, calm as ever. His plan was coming together nicely so far. These weapons he's collected have been rumored to take out the Avengers.

Once he's made a pass through the base, certain that everyone is in their locations, he makes his way back to the security room. There, he can watch and wait for their arrival. After all, he made sure to 'accidentally' leave behind evidence for the superheroes to pick up on him.

The security room was as one would expect. Just room with a bunch of screens showing different camera feeds. Rumlow sat on the chair and kicked back, resting his feet on the table.

It took about an hour for any sightings to happen. And finally, it happened. He spotted movement through the woods just outside the base. Rumlow smirked, reaching for his walkie talkie. "They're here. Prepare yourselves, boys. This'll be the greatest day of our lives!" he said into the receiver.

Outside, the Avengers sat in various hiding spaces. The leader and co-leader, Tony and Steve respectively, were behind a bush. Tony was using his tech to scan the base to see just how many enemies were in the base.

"There seems to be some. Not too much but you never know with these octopus goons. They could be hiding something - and I mean something other than those weapons, quit giving me that look."

Steve chuckled, turning his attention back towards the base, Tony scoffing at him. Ignoring the genius, the super soldier just reached a hand up to his comm.

"Alright. We all know the deal. We break in, get the weapons, and get out. Anybody that isn't us gets taken down," Steve ordered. He could hear the rounds of affirmatives.

Steve already knew that there would most likely be some sort of competition between Thor and Hulk as in who could take out more enemies.

He and Tony were the first to enter the base, the lock no match for Tony's suit.

Tony narrowed his eyes slightly, feeling a sort of unease. Hydra's locks were never this easy to break.

Something was wrong.

He just couldn't put his finger on it.

"Jarvis, rescan the base," he said, holding out a hand to stop Steve from continuing inside. He didn't care if this caused a delay. If this meant not walking into a trap, he would cause as many delays as it takes.

It took only a moment before Jarvis responded. "Sir, there seems to be some sort of interference. I cannot scan for anything."

Tony looked at Steve, his eyes wide, though Steve couldn't see them due to his face mask. Steve reached up to his comm. again. However, there was the alarming sound of static that meant interference or no signal.

"Great. Just fucking great," Tony cursed.

"La-"

"Don't even start. I know you're thinking the same thing."

Steve opened his mouth to say something, then must have realized he was right, because Tony watched him close it and face forward again.

Tony just smirked. "Anyways, we're the Avengers. We can get through anything Hydra, and any other enemies, throws at us. Have faith in us. Have faith in our team."

Steve just sighed. "Yeah, I know… It's just, if we can't reach the others to warn them… Who's to say they won't try something? What if they-"

"They won't! We won't let them. Okay? Sam will protect Bucky, and Thor will protect Lydia. They won't even be able to utter the end of the first word," Tony assured firmly, yet gently.

With a nod from the super soldier, the pair continued forward, Steve with his shield ready to defend/attack with, and Tony with his repulsor blasters charged and ready to shoot.

o0o0o0o0o0o

On the other side of the base, Clint and Natasha crawled into the base via the vent systems. Natasha being in front of Clint. They crawl through until they find a vent cover to crawl out of, with no Hydra soldiers in sight. Careful to not make any noise, Natasha opened the cover, and the two spies hopped down silently.

Clint looked around at the room they were in, blinking. "This… is quiet."

Natasha, who was trying to contact Steve to let him know they were in, turned to the archer. "Communications are down. We're on our own, for now," she said.

"Interference or something?"

"I have a feeling it's more than just that, Clint. Something's wrong here."

o0o0o0o0o0o

The rest of the team were going in through the back entrance. Lydia was listening to Thor and Hulk talk about some sort of bet, but she didn't listen to it all that much. Most of her attention was focused on the task at hand, anyways. Sam was controlling Redwing, who he had flying on ahead to scope the area.

Bucky himself was a little uneasy about this mission. He just had this feeling, that something was going to happen. He just… couldn't put a finger on it. With a quick glance to his teammates, he could tell his sister had the same uneasy feeling. Which, usually, meant one thing.

"What do you smell, Lyd?" he asked, his tone silencing Thor and Hulk.

"... How many exactly was said to be here?"

"About 7. Why?"

Lydia shook her head. "I smell way-" she was cut off by a bullet hitting the wall too close for comfort. She ducked down, while Bucky spun, aiming his gun at the culprit and pulled the trigger.

The fight has started.

o0o0o0o0o0o

Back in New York…

A kid was running down the streets, pushing past people, crossing without looking, lucky to not getting hit by any cars. Right now, he had to hurry. As fast as his legs could carry him. For his mission was to find someone.

For what, he didn't exactly know.

All he was told by the mysterious man who looked like a wizard, was that this man was needed urgently. That his friends were in danger.

The kid paused, looking around once again in case this person he had to find was walking about.

When he didn't spot him, he turned to run to his destination again, only to bump into someone. He let out a small 'oof' as he landed on his butt. He glanced up to see someone wearing armor that looked to be of another world, holding a sceptor.

He found him.

"Mr. Loki?" he asked, standing up.

Loki had looked down when he felt someone small run into him. And now, he was curious as to how this kid new his name. Probably the media, no doubt.

"Yes?"

"Okay, good! I found you! Quick, some wizard guy told me to find you. Said something about friends being in danger!" the kid rushed out.

"Where?"

"I don't know, he didn't tell me."

Loki nodded. "Thank you, small mortal child. I will see to this matter."

o0o0o0o0o0o

Back at the Hydra base…

The Avengers were fighting for their lives in the main weapon room. Somehow, the Hydra soldiers had powered up enough to overpower them. This didn't bode well at all.

Rumlow grew tired of the Avengers' will to survive, so he went to one of the weapons. Grabbing one, he took aim and shot.

His first target was a successful hit.

The screams from the Hulk startled the other Avengers enough for Hydra to gain more of an upper hand. Rumlow took aim once more, hitting Steve. The super soldier went back-first against the wall before falling to the ground, unconscious. Natasha and Clint were the next to victims to the weapon, and they landed on the floor as they were hit.

Rumlow smirked, happy that his plan had worked. His attention then turned to his next victim, watching as Lydia finished off one of his men. He aimed the weapon for a headshot, and pulled the trigger.

However, it didn't hit the intended target. Instead, someone had appeared next to her and created a force-field to block the shot. The culprit looked at him with fury in his eyes. Rumlow felt his stomach drop.

Loki stood there in his Asgardian armor and scepter in hand, and his fury was turned on Rumlow.

"You were unwise to harm these good people, Mister Rumlow," Loki growled, gripping his scepter tightly.

"Why did you even bother to save her? Especially since you did attack them not so long ago," Rumlow asked him.

"My business is of no matter to you, mortal. What does matter, however, is that I am here now, and you will not harm them any longer!"

Unbeknownst to Rumlow, Loki had merely been distracting him long enough for his brother to get behind him and attack. Thor brought Mjolnir down, but Rumlow managed to duck in time. Cursing his luck, he quickly activated the self-destruct feature before tossing it at Bucky who had charged at him.

"No matter, you will all die here!" Rumlow said, pulling out a remote and pressing a button, causing himself to teleport out of the base.

The clock on the weapon display read 0:10. No time to escape.

Lydia stumbled over to Thor and Loki, her leg having been injured during her fight against some of the Hydra soldiers. "What are we going to do?"

0:09

Tony landed beside them, faceplate coming up to show his face, his expression full of fear and resignation. Just by that look alone, the team knew there wasn't any hope of getting out of this alive.

0:08

Bucky and Sam came over, the two of them dragging Steve, Natasha, and Clint over with them. Might as well die in a group instead of scattered, right?

0:07

Thor went to drag Hulk over. He never thought it'd end like this. Trapped in a place about to blow with no chance of survival. Sure, he could've called for the Bifrost, but he wouldn't leave anybody behind. Not ever.

0:06

Tony, despite knowing he couldn't, started to see if he could disassemble the weapon to try to stop the self-destruct timer.

0:05

Lydia just sat on the ground, tears streaming down her face. At least she'd be able to join her family in the after life, right?

0:04

Thor sat next to her, bringing her into his arms. Holding the woman he loved, wishing he could tell her. Wishing it wasn't too late.

0:03

Loki, looking at his scepter, sighed. While they may not escape, maybe he could create a strong enough force-field to protect them.

0:02

With no time to react, Loki kicked the weapon out of Tony's grasp, and away from the pile, creating a force-field bubble around them. And not a moment too soon, as two seconds later, the weapon went off, causing a devastating explosion.

Rubble falling from the ceiling landed on the force-field, bouncing off until Loki's magic flickered out, Loki growing tired from the prolonged use after having been cut off from it for a while. The collapsed building buried the surviving Avengers.