Hey everyone! Just a quick side-note, if something is written with speech marks and in italics, "like this," it means a character is speaking in another language. In the case of this story, both Percy and Jason can speak Latin and Ancient Greek, and none of the Avengers, even Natasha, can understand or speak either of them. Okay that's all!

"Hey wait! What's going on?" Percy called, as the Avengers all stood up and headed hurriedly over to the lift.

Another crash was heard. Percy and Jason ran to the window and looked outside. What they saw was worse than they could have imagined.

There were windows in some of the shops smashed, cars turned over, some even on fire. People were running about in a panic, screaming. But the worst sight of all was what was causing it.

Their eyes fell on the 5 headed, fire breathing beast. "Hydra," Percy whispered.

Their attention was pulled away from the window when they heard the lift doors opening. They whipped round as they saw the Avengers step in.

"Wait! You have to let us help!" Percy shouted at them. Natasha scoffed. "Nice try, kid, but we're not going to just let you walk outside with the distraction of, whatever that thing is," she said, gesturing to the window.

"But you don't know what you're dealing with," Jason tried. "And you do?" challenged Tony, who was walking out to the large balcony area.

"Sorry guys, but there's not a chance you both are going out there. It's way too dangerous," Steve said firmly. Before they could argue further, the doors began to close.

"Watch them, and don't let them out of your sight," Natasha called to the agents stationed in the room, who nodded in return, just as the lift shut. Percy and Jason turned back to the window just in time to see Tony fully suited up (how on earth did he change so fast?) and jumping off the edge of the building towards the monster waiting below.

The two looked over at the agents, who were firmly at attention, then back at each other, before switching to Greek.

"What do we do? There's no way they'll be able to defeat the Hydra, and those guys won't let us move a muscle without raising their guns at us," Jason said, gesturing to the agents, who looked utterly bewildered at the conversation, "but we can't just leave them out there! They'll be killed!" he continued, clearly frustrated by the situation they were in.

Percy could understand his annoyance. They hadn't been with the Avengers that long, but he really thought they would have let them go by now. That was the only reason he hadn't tried to escape; figured it was better to get them to trust him so they would clear the suspicions against him, and he could leave without having to hide from the government as well as monsters.

Clearly, though, none of that had happened yet. Although he supposed they wouldn't have been able to escape anyway, seeing as they wouldn't let him and Jason be alone together long enough so that they could formulate a plan.

On top of all this though, Percy had a bad feeling. No one had tried to contact them since their capture. Maybe they were just busy, and Percy was being paranoid, but something still felt wrong. He just hoped they could get out of here sooner rather than later to ease his mind of his worries.

He felt at his pocket, feeling the familiar outline of Riptide. He hadn't had it in a while, since the outfits they had been given at the start of their capture had no pockets. However he had been able to grab a new pair from the extra clothes that were in the changing rooms of the pool, and they, luckily, did have pockets, causing Riptide to appear soon after he put them on.

He glanced at the agents before replying. "I know. We have to find a way to get down there." He looked around the room before his eyes landed on the sprinklers overhead, and a grin grew on his face.

Jason followed his gaze and gave a smirk of his own. "Take it away, Son of Poseidon," he said stepping out of the way. "Why thank you, son of the queen of drama," he responded. He hesitated for a second for the inevitable roll of thunder and was surprised when none came.

Jason looked surprised as well, but he just shrugged and let Percy do his thing. They'd worry about why Zeus wasn't taking every opportunity to threaten him later.

Percy turned back to the sprinklers and focused on the water running through them. He gripped on to it and threw his hands down. The water immediately splashed down all over the agents.

They started shouting in confusion, providing Jason and Percy the perfect opportunity to run to balcony and jump out, Jason flying them both down to the battle below.

...

"What the heck is this thing?" Tony yelled through the coms. When they had all arrived at the base of the tower and ventured out on to the streets, they had been in complete shock.

They hadn't known what they were expecting, but it certainly wasn't an oversized lizard that could breath fire! And did it have multiple heads?!

It was big, nowhere near the size of a regular sized lizard, and breathing fire at each of them at once. Hulk joined the fight, seeing as he was the only one who wasn't like an ant compared to the thing.

"I have no idea, but we have to stop it now. It's tearing up the streets!" Clint shouted into the commlink.

"Tony, you fly up and keep it distracted. Clint, you try and see if you can find a weak spot on it," Steve ordered. They both did as told, Tony shooting at it from above while Clint shot form below.

"I don't think I can keep this up for much longer. You getting anywhere, Barton?" Tony asked while avoiding blasts of fire.

"No. I can't even make a dent in it," he answered through grunts of ducking to avoid being swallowed whole.

"We better find a way fast, or else- Tony there's something coming up behind you!" yelled Natasha, causing Tony to veer off course. He collected himself and glanced upwards. She was right. Something was coming towards them, fast!

"Great, now we have to deal with two monsters!" he said, taking cover behind an upturned car.

"Wait, that's not a monster. It's Percy and Jason!" said Steve, staring up at the approaching figures.

Sure enough, moments later, the two boys landed on the road. Clint and Natasha kept the beast busy as Tony and Steve ran over to them.

"What are you doing here?" Tony yelled, still shooting blasts at the giant lizard.

"We're here to help," said Jason. "Sorry kid, but we're not letting you anywhere near that thing. We can't even hurt it. I don't think you'll be much help," said Steve.

"You don't understand, we can defeat-" Percy started but was cut off by another roar and blast of fire.

They hurled the boys out of the way. "Stay here," Steve commanded, before he ran off to re-join the fight. Tony bent down, grabbed the boys hands before they could stop him, and cuffed them to a lamp pole.

"Hey! What are you doing?" Percy yelled at him. Tony began to walk away. "You're far enough away that you'll be out of the fight, but we can't risk letting you both get away. We'll get you when we're done," he said, before turning and flying away.

...

"You have got to be kidding me," Percy groaned, struggling with the restraints. "We have got to get out of these," said Jason, looking around for something to pick the lock. "Really? No way, what made you think we had to do that," Percy said sarcastically.

Jason gave him a look, but didn't say anything. He knew Percy was just frustrated. He was too, but getting annoyed wasn't going to solve anything.

As Percy kept trying to maneuverer his hands out of the cuffs, Jason's eyes fell on a drainage entry point where all the water goes in a flood. An idea came to him.

"Percy, can you reach that drainer over there?" Jason asked. Percy stopped his struggling and followed Jason's gaze. "Yeah, why?" he questioned, looking at him weirdly.

"Pull some of the water up here and over to us," Jason ordered. Percy looked at him for a moment, not getting where he was going with this, before moving his head (seeing as he couldn't use his hands) slowly upwards, pulling a stream of water up from the underground.

Jason nodded at him once he had brought it over to them. "Good, now put it around the cuffs and freeze it." Percy snapped his head towards him, with a look of disgust on his face. "Dude what? No! That water came from the sewers," he complained, giving the water a disgusted look.

Jason rolled his eyes. "For gods sake, your dad is the God of all water. How can this gross you out?" Percy gave a look of defeat before lowering the water onto his cuffs. "Still gross," he mumbled.

"Why am I doing this again?" he asked before blowing onto the water, freezing it over. "By freezing the metal, it becomes more brittle, and prone to breaking.

Once the cuffs were completely frozen, Percy raised his hands up before smashing them on the ground, causing the block of ice to shatter instantly. His eyes widened, impressed.

"Huh, you're smarter than you look, Grace," he said before repeating the process on Jason's restraints. "You're too kind," said Jason, sarcastically. Soon enough, they were both free.

"Right, let's go help these so called heroes," said Percy, before they both ran out to join the fight.

….

It was not going well.

The Hydra had Tony trapped in its claws, Natasha had just been thrown off, sending her flying down the street (how she had even got on top of the thing, they had no idea) and Clint and Steve were simply trying to avoid getting burned.

The only reason Tony hadn't been eaten yet was because The Hulk was actually giving the monster a run for it's money, distracting it from the rest of them. It was weird seeing Bruce's other half, a complete opposite to the man they had met the night before.

"Okay, what's the plan?" Jason asked, turning to Percy. "Why am I the one who has to come up with a plan?" he retorted. Jason shrugged. "Everyone is always saying what a great leader you are," he replied innocently.

"Fine," Percy grumbled in response. "I'm always the one who has to save the day, and save everyone else," he muttered, clearly done with this already, but quickly snapped to attention.

"Okay, I'm gonna take a wild guess and say that thing is here for us," Percy began. Jason rolled his eyes. "No, what gave you that impression?" he said sarcastically.

Percy glared at him, but sighed. "Anyway," he continued, "because of that, it's probably looking for us, which means we can draw its attention away from the others and onto us. Once we do that, I'll keep its focus while you fly up and chop off its heads. Then we'll burn the stumps and ta da! Dead Hydra."

Jason nodded. It was a solid plan, but he had one question. "Where are we going to get fire from?" he asked. "I'm willing to bet he has some kind of flame thrower in that suit," said Percy, nodding his head at Tony.

"That's a risky bet," Jason replied, unsure. "One I'm willing to take, as your honourable leader," Percy said with a smirk, before standing up and jumping out to join the fight. Jason was right behind him, rolling his eyes but grinning all the same at Percy's antics.

"How do you two keep escaping?" Clint questioned in a raised voice over all the roaring and fire breathing, once they appeared beside him and Steve.

"Built different, we've been over this," Percy called in response. They were ducked behind a car for cover. "Okay we have a plan; what we need to do is-" Percy began.

"No, we've been over this," said Steve. "You two are staying here. Clint, let's finish this," he said, before the two jumped over the car and raced to the monster.

"Now, Tony!" Steve yelled. At this point, Tony pressed his hands on the giant claw holding him, the palms lighting up before a large blast echoed through the streets.

The Hydra roared and dropped Tony, who caught himself and flew up above the heads, right before the chaos ensued.

...

Steve threw his shield right at the monster's neck, slicing through 2 heads at once.

"No!" Percy yelled, racing over to try and stop them. Tony fired blasts from above, allowing Steve to jump on Clint's back who launched him high into the air. He landed on top of the Hydra and brought his shield down with such force that cut right through, causing the beast to roar out.

"Stop!" started Jason. The head fell to the ground. "Cutting!" And another dropped down. "Heads!" he yelled out, as the last one rolled to his feet.

Steve jumped down as the monster collapsed. Tony lowered himself to the ground as the rest all walked over, covered in dirt, grim and blood. Yet they were all smiling with pride.

"Nice one, Steve," said Nat, punching him playfully in the shoulder. "Thanks, but it was all of us," he replied. Tony flipped his mask up so his rolling eyes could be seen. "Yeah, yeah, you're Mr Humble and all that."

It was at this point that they noticed the two very angry teens stomping up to them.

"What's up with you two?" Clint asked. "And how did you get out of those restraints?" added Tony. "You idiots," Percy said with a pained look on his face.

"Hey, we're the ones who just stopped that thing. A little thanks wouldn't be too much to ask for," said Tony. Jason shook his head. "No, you haven't."

Natasha frowned. "What do you mean?" she asked, slightly concerned. Jason looked up at her, but moved his head to look past her, staring.

"When you chop off 5 heads...," he began. It was at this point they noticed the sound of movement behind them.

They slowly turned around to see the body of the creature standing back up, new heads growing back on. "... 7 more grow back," he finished.

...

The Hydra's eyes landed on the group. It flicked its tongue and roared, launching its heads forward. They jumped out of the way only just in time.

"How the heck is that thing still alive?" Clint yelled over the noise. "This is why we told you to listen to us!" Percy shouted back. He turned to Tony kneeling beside him, ready to blast at the Hydra again.

"Hey," he said, gripping his arm. Tony looked at him but didn't lower his hand. "You got any fire weapons in that thing?" he asked. Tony stared at him for a second, before nodding. " Yeah..." he said uncertainly. "Why?" Percy glanced briefly at the creature prowling around, looking for them. "When we give the signal, fire where we slice, at the stumps of its neck," Percy ordered. "I thought you said not to cut off its heads!" Tony exclaimed. Percy was about to tell him to just do it when he was forced to dive to the side as a large tail came crashing down right where he had been, causing him to roll out right into the open.

He got up, turned round and froze. The monster was staring right at him, mouth wide open with what looked like glee.

"Perseus Jackson," it hissed at him, although only he and Jason could hear. "I knew there was a powerful demigod here, but I didn't realise it was a Son of Poseidon," it continued, before glancing over at Jason who was watching the interaction. "And a son of Jupiter? My lucky day. You both will be delicious."

Percy glared at it. "Yeah, no thanks. Getting eaten by an ugly oversized lizard is not on my to-do list for today," he said casually, not breaking eye contact. That did not sit well with the Hydra. It's look of glee turned into a snare. It hissed, and Percy could feel the heat rising in it's throat before it even escaped the beasts mouth.

Percy lunged out of the way, but was not prepared for the the second head waiting for him, or the painful burn that followed.

He gripped his shoulder, gritting his teeth through the pain. "Alright. You want a fight? I'll give you a fight," he muttered before slowly standing up and pulling out his pen. He uncapped it and Riptide appeared in his grip.

Jason suddenly emerged beside him, ready to join Percy in taking down the monster. "Ready?" asked Percy. Jason floated slightly off the ground. "Oh yeah," he replied before they both launched into battle.

...

Jason flew up into the air, over the Hydras heads. Percy swung his sword while dodging fire attacks and sharp claws. He watched carefully, waiting for the perfect opening. Thanks to Percy being such an amazing fighter, he didn't have to wait long.

He managed to get all the heads to focus on him at once, allowing Jason to plunge into the centre of them.

Percy threw his sword through the air. Jason caught it and started decapitating the monster. "Now!" yelled Percy at Tony, who began using what looked like some kind of fire launcher at the stumps of the necks.

Jason tossed Percy's sword back to him, as he was currently surrounded by the remaining heads. He caught it and in one swoop, cut clean through all of them at once.

Tony appeared and burned those as well. Soon enough, the monster had collapsed in a heap on the ground. Jason landed softly on the ground, and Percy walked up to him, followed by all the Avengers, who looked completely dumbfounded.

"Um, what just happened?" asked Bruce, who was currently sporting ripped sweatpants and a long coat. "How did you both do that?" said Steve in awe, staring at the now dead monster.

Jason scratched his head awkwardly. He had no clue how they would get out of this. "Um exactly did you guys see?" he asked hesitantly.

They looked at him confused. "What do you mean?" questioned Natasha, looking at them wearily. "What do you think you were fighting?" Percy explained.

They looked between themselves. "Well, I have no idea what it was, but it looked like some giant lizard," stated Tony. "But don't lizards only have one head?" persisted Clint. "Well, there have been some cases in the wild where reports were made of 2 headed animals, maybe even 3," Bruce suggested, deep in thought, trying to make sense of the situation.

"I'm pretty sure this thing had more than 5 heads though," said Clint, clearly not convinced. He turned to the boys, arms folded. "You both seemed to know how to stop it, do you know anything about this thing?" he asked expectantly.

Jason and Percy were holding their breath, praying to the Gods the mortals would believe whatever lie they could come up with. They glanced at each other, before Percy slowly spoke.

"Maybe, it was something that escaped from a government facility. Don't they experiment on animals, or aliens in your case?" He said this looking at Natasha. She narrowed her eyes at him.

They obviously didn't know for sure if S.H.I.E.L.D did that, but he wouldn't be surprised.

As if they were listening (which again he wouldn't be surprised at) and before anyone could answer, multiple black SUV's and Jeeps raced into the now deserted street, except for the Avengers and demigods of course.

They screeched to a halt, the doors bursting open and agents rushing out from each one, along with a very annoyed looking pirate. Seriously is this guy ever not mad?

"Get down on the ground now!" an agent yelled at the two. They did as told, not wanting to start a row, but even so the agents pushed them down to the ground hard.

They grunted in discomfort at the gravel scrapping their faces. Jason could see Percy, their faces on their sides. He heard, who he guessed was one the Avengers, start yelling at the agents to stop, asking them what they were doing and whatever other nonsense they were wanting to say to pretend they cared.

They were hulled to their feet, their hands in much more techy cuffs this time before being walked to the entrance of the tower. There was a lot of shouting and people running about, when all of a sudden, it stopped. Silence.

Percy and Jason looked at each other, confused. They peered around them, noticing everyone was frozen. "Well, guess you figured out who the Avengers are," a voiced said from in front of them.

They whipped their heads back to see... the teenage boy Jason had met in the park. Jason squinted at him. "You again? Are you doing all this? What are you, some kind of time stopping monster?"

"Dude!" Percy stage-whispered. Jason shook his head in confusion at him. "What?" he asked. The teenager in front of them laughed. "I thought I told you to stop being so serious. And always being in monster-battle-mode is pretty serious," he said jokingly, walking closer. There was something familiar about him, but Jason couldn't pinpoint what.

He looked at Percy and nodded. "Good to see you again Percy," he said grinning. "Yeah, likewise Apollo," said Percy, returning his nod.

Jason's eyes widened. Wait what?! "Apollo? As in the God Apollo?" Jason questioned, staring at him. "The one and only," Apollo replied with a dramatic bow. That's why he looked familiar. He looked like Will!

"What are you doing here?" asked Percy. The smile dropped from Apollo's face. He looked at them gravelly.

"Not for good reason's I'm afraid," he responded. "Something terrible has happened; is happening." Jason and Percy glanced at each other. "What do you mean? What's going on?" asked Percy, already sounding worried.

Apollo looked between them before speaking. "When you defeated Gaia, we thought that was it. The Gods thought that was it. But we were wrong. She used her lance ounce of power to ensure we wouldn't truly win." He paused, unsure how to say what he needed to.

"Lord Apollo, please, what did she do?" pleaded Jason. He wished he hadn't asked. Apollo met their eyes. "She sent a plague."

Jason's eyes widened, as did Percy's. "It's killing, everyone, and I don't know how to stop it," Apollo said, voice breaking, looking down. "But you're the God of medicine! Surely you can figure out something," cried Percy.

Apollo shook his head. "No, I can't. I've been trying since it started. But it's spreading so fast. Percy, Jason," he said, looking up at them. "It's wiping out the demigods."

Jason choked. How could this be happening? And how did I not know? "When did it start?" Jason asked, trying to keep his composure. "A few days ago at Camp Half-Blood, with a young demigod, Johnny," Apollo explained.

Percy gasped beside him. "Is he..." asked Percy, worry clear on his face. Apollo looked at them with an expression that told them everything. Percy looked away with his eyes shut. Jason didn't know the boy, but it was clear Percy did.

Jason shot him a concerned look, before asking, "Does this have anything to do with the Iris Messaging problem?" "Iris Messaging problem?" Percy quietly asked, confused. Apollo nodded. "Yes, it is why no messages have been able to go through between Gods and demigods. Gaia is somehow blocking any and all communication, most likely in the hopes that others will leave Olympus or the camps in order to check on everyone else, which is why I had to come to you."

Percy turned back at this point. "I can't stay much longer," said Apollo, at which point his form began to flicker. "It's taking all my strength just to hold this scene. When I stop, the mortals will see me, which is why I wasn't able to speak with you until now. I could only communicate in person, and there was no way I would be able to enter that building without the mortals knowing. With the strength of this disease, I haven't had the power to speak with you in private until now," he said, gesturing to the scenario around them. Even as he spoke, Jason could see people starting to slowly move again.

He hurriedly turned back to face the god. "You have to get us out of here, so we can help," said Jason quickly, desperate to speak before he disappeared. Apollo shook his head. "I can't that's why I'm hear. To warn you. You two are the most powerful and important demigods in existence. If you go back, you could risk catching the plague, and spreading it even further. You both could, would, die."

"But we must do something! We can't just leave everyone to die!" Percy argued. "No," Apollo said firmly. "We've all agreed. You two are far too important to risk being killed by this sickness. There is a good chance you will die young, but it cannot be because of this. Your time is not yet over."

"Thanks, that's real encouraging," Percy said sarcastically, clearly angry with the situation. Apollo looked darkly at them. "I'm serious."

"So am I! If you think we're just going to sit here-" Percy began, voice rising. "Percy!" Apollo shouted. Percy quietened as Apollo looked between him and Jason. "The Fates did not foresee this happening."

They stared at him. "But," Jason began, "they see everything. How could they not know of this?"

"Because it was not meant to be. This plague... it has no cure. No cure, no more demigods, or civilisation. No civilisation..." Apollo explained. "No more Gods," finished Jason quietly.

Apollo nodded, his form beginning to glow. "I must go. I will not be able to contact you again, but you cannot go to camp, no matter what," he said, his voice already becoming an echo.

Before either of them could protest further, a blinding light forced them to look away. When they, turned back, time had begun again, and there was no teenage boy standing before them.

They felt themselves being shoved forward, causing Jason to stumble slightly, before being roughly up righted.

"Wait! Let us go! You have to let us go! Please" yelled Jason, trying to turn his head to look for the Avengers, hoping that maybe they might help them, listen to them.

But no such luck. Instead, he and Percy were forced into the building; away from any chance of escape, or from saving their friends.

Hey everyone. Just want to clarify something. I am aware that only celestial bronze, imperial gold and stygian iron can hurt a monster (as in not mortal weapons) but I decided that the rules for this version of the universe is that beings with a unnatural level of strength, aka Steve, with the use of his weapon being made from the strongest mortal metal on Earth, would be able to damage a monster temporarily, but not permanently, so you would still need the God's metals to defeat a monster. I figured this way it would still keep the importance and necessity of Percy and Jason's weapons, but allow this scene to make sense. Hope that's okay with you all!