"Can you...hear that?" Simmons asked as she perked her ears, listening to the distinct humming sound that was slowly filling the air. Beside her, Fitz was doing the same. They both dropped their tools in order to listen better. The had been in the middle of examining the available data they had on the mysterious X-23. Tests that now seemed to take a back-seat to getting her to talk.

"It sounds like a helicopter," Fitz reasoned with a shrug.

"It's to loud for a single helicopter. More like a hundred," Simmons said as her eye darted from side to side. "And S.H.I.E.L.D would never allow more than ten in the air at a time..." she continued as Coulson burst into the room. He looked sweaty, as if he had just run for his life.

"Down!" he shouted, and the two scientists obeyed him without question. He was a senior field agent, after all, compared to their status as mere scientists. And on top of his orders, the entire building shook, as something impacted the side of the Triskellion. "That was to close," Coulson muttered under his breath as he pulled the two of them to their feet. "We've got only one wall between us and the missiles," he grunted as he shoved them out the door, "Move!" A second explosion rocked the building, sending Simmons to her knees. Fortunately, Coulson helped her back up.

"Where are we going?" Fitz stammered, his voice dripping with absolute panic.

"Bunker," Coulson replied as he spun them around a corner. "It'll be able to take anything they can throw at us," he continued as a fire-team of agents hustled down the hall, opposite them. They all carried heavy-duty weapons and mechanized combat gear. Simmons guessed that a single uniform and rifle weighed almost as much as she did. If there was any force that she felt could protect them from any threat, it was S.H.I.E.L.D. So long as they weren't on the front lines. Which was where she was sure the rest of the team would be.

"Where are-" Simmons began to ask.

"McFarlane and Thompson are on the upper floors," Coulson stuttered as they veered around another corner. "They headed for the R.P.G's right away. Stacey and Spider-man where in the training rooms below us. Agent Drew was meeting with the director and Pryde is M.I.A, after a spat with Danvers," the senior agent finished as they thundered down the hallway. As they reached the halfway point,a loud roar echoed through the halls. A split second later, a single S.H.I.E.L.D agent, wearing the remains of a mechanized armour set, sprinted down the hall, and took shots at a seemingly invisible target.

"They're everywhere! They're everywhere! Run! Run!" the man screamed with a blood-curdling tone as his arms went into spasm. Coulson was forced to restrain the man as the two scientists huddled in a corner. "Run while you still can! They're everywhere! They'r-" Coulson's hand smacked against the man's mouth, silencing him instantly.

"What happened?" Couslon growled as he held the man tightly. The man didn't answer, he simply shook his head and closed his eyes, as if what he saw was too terrifying to talk about in any regard. "Keep moving!" he ordered as he released the man, and thundered down the hall again. Once more, the two scientists followed him without question. Unfortunately, they followed him right into the path of a group of three eight-foot tall men covered in blood, and wearing a savage grins. Each man seemed to have more muscle than the last. And they all seemed to mach Agent Thompson's description of the being who had attacked them. They where all naked, save for a synthetic, rubbery fabric around their hips and upper thighs. And they all had what appeared to be a serial number tattooed across their chest. X-41, X-45 and X-49 roared viciously before charging them. Coulson fired his weapon twice before turning and running, along with Fitz and Simmons. They weren't fast enough, however.

But Katherine Pryde was. She slipped out of the floor long enough to grab the three of them, before pulling them back down into the basement. Above them, Simmons could still hear the savage cries of their attackers. Apparently, they where desirable prey, which was why she refused to stand still, and began to make her way further inwards, only for Coulson to grab her by the shoulder and shake his head.

"That way's not safe," he said with a slight pant.

XXX

"Any Idea what these things are?" Miles shouted as he ducked under a swiping blow from one of the beings. This one, unlike the others, was much smaller, around the size of an average human being. But much more deadly. On it's chest was a tattoo that read 'X-25' which confirmed it's relation to the prisoner from the Mutant Island. Beside him Agent Venom was weaving around another being with the marking 'X-32' etched on it's chest. He trusted her enough to watch his back, if only because he had no other choice.

"No," Agent Venom replied swiftly as she formed her hand into a blade, and sliced her opponent's shoulder. "But they aren't fully human. Looks like-" she was cut off as a third soldier, 'X-30' leaped in between the two of them. Miles slipped under it's arm as he delivered one of his bio-electric shocks to it's sternum. Normally, that would have been enough to paralyse a person on the spot, but X-30 shrugged it off as if it was nothing. That was further proof that they weren't fighting humans, but meta-humans. Possibly mind-controlled mutants.

"Hruuaarrgg!" 'X-32' roared as it slammed a fist into Mile's stomach, and sent him through a wall. He rolled back to his feet, only to find a small trickle of blood coming from his thigh. Great, he thought as he webbed up the wound, now there's that to deal with on top of everything else and- he was cut off by Agent Venom crashing beside him, looking equally dazed. Before either of them could react, however, the roof collapsed to their left, revealing a struggling Ms Marvel, who was set against an 'X-26'.

"Run!" Miles shouted, knowing full well that they where out-matched, and that staying and fighting was suicide. Agent Venom took his advice and they both ran down the hallway, followed closely by Ms Marvel, who covered their escape as best she could. They turned a corner and nearly ran straight into Agent Thompson and Agent Mcfarlane, both of whom carried assault weapons. Behind them, Miles instantly recognized Nick Fury, the director of S.H.I.E.L.D, along with two more agents. One of whom was being carried by the other.

"We're abandoning the base," Fury barked as he indicated towards the nearest exit. They all burst out into the sunlight, and raced along the landing pad. To their left, Coulson and Pryde lead the two scientists out of another exit, and towards the nearest helicopter. As soon as they were less than five hundred feet from it, however, it began to move.

Not under it's own power, however. It was being lifted by something. Someone. An eight-foot tall brute with the serial number 'X-50' etched across it's chest. Now, more than before, the fight was on.

Ms Marvel and Agent Venom where the first to rush into the fight, given that they where the two strongest and fastest. Agent Venom went down low, while Ms Marvel went up high. But they both missed, as X-50 managed to perform a corkscrew spin in between their bodies. What was more, was the fact that it also landed two heavy blows against them both before they could fully recover. Knowing he was needed, Miles raced forward and managed to web X-50's feet together and deliver a solid punch to it's stomach. However, the blow did little to phase it, as Miles brought his numb hand back, feeling like he had punched concrete. He ducked under a sweeping strike, though only by a hair, as the creature was almost as fast as he was, and tried to sweep it's legs out from underneath it. But this time, X-50 leaped over Miles' head and axe-kicked him halfway across the landing platform. The blow had hit him like a train, and he felt a swelling of pain coming from his sides. He winced as he tried to get back on his feet, as Agent Drew rushed past him, along with four more S.H.I.E.L.D agents.

She tried the same thing that he did, and webbed up X-50's legs before striking him. She seemed to have some luck, however, as the brute backed up by a foot before re-gaining it's balance, and swiping it's massive fist in her direction. She evaded, though only barely, and delivered a series of quick strikes to it's side before being forced onto the defensive, just as Ms Marvel re-entered the fight by delivering a powerful uppercut to it's chin. For a brief moment, Miles thought that maybe the two of them could win against the brute.

But that was before six more 'X's' burst onto the landing platform, and roared viciously.

XXX

Sounds. That was what she could hear. Sounds. Just sounds. And there where no bodies around to make those sounds. Not Kong. Not Coulson. Not Simmons. Not Fitz. No one. They had run fast, away from her. Like others had, before she had been brought to the place. But still, the sounds came.

Sounds that she remembered hearing at the place they had kept her before. The sounds of her pack. She sniffed the air, and could smell them all, from the leader to the first one. She knew they where all here, to hurt the people who had been nice to her. To hurt the people who had not hurt her. So, she had only one solution. She brought out the long, sharp claws, and cut herself free, which she could have done before, but didn't. She liked it here, among her 'friends'. And she knew she had to save them from her pack.

So she ran out into the long tube that lead northwards. She could see through a portion of the tune. She could see her friends fighting the Pack leader. And she moved faster, because she knew that he would kill them all. He was that strong. He was the pack leader for a reason, and that was his strength and cunning. She moved faster and faster, out into the sunlight, along the long, metal surface, and past several more of her pack-members. She stopped only to strike the ones that where in her way, because she had a goal. She had to get to the Pack Leader. And she did.

She jumped high and landed on his back, and began to slash away. He threw her off seconds later, and roared viciously at her. She snarled back, challenging him as she swept her claws towards his face. He moved out of the path of her strike, and struck back. With his longer limbs, he was able to hit her, and knock her aside. But she got back up quickly as the smell in the air began to change. She looked upwards, and saw the area was getting much darker, and something sprinkled against her face, and something else made a very loud noise in the distance.

But she paid those things little attention, as she tried to strike the Pack leader again, only for her arm to be grabbed, and for her to be tossed away, into the air. She landed at a man's feet. This man was not familiar to her. He wore strange clothing, and carried a round piece of metal in his hand. Beside him stood another man, with a metal weapon that was larger on one end. And on the first man's other side stood a piece of metal that was in the shape of a man.

"Take them down!" the first man shouted with a battle-cry.

A/N: Up next: Can the Ultimates defeat H.Y.D.R.A's super-soldier army? Can they even survive the wrath of the dreaded X-50?