(A/N: I've started my Attack On Titan fic. I've been wanting to write one ever since I saw the anime. For those of you that read the manga, this story takes place during the time between the Female Titan Arc and the Class of the Titans Arc. If you haven't read the manga, that's ok, just know that this story takes place after the anime. I am sorry to say that this story will be a shorty one, maybe about 30,000 words, and about 7 or 8 chapters, but we can enjoy it while it lasts. So, without further ado, lets get started.)

Disclaimer: I own nothing.

"TITAN X"

Chapter 1: Secret Meeting

They didn't know why they had been called here, only that the safety of the entire human race was at stake. At least that's what the mysterious letter they had received claimed. The letter was from some named Dr. P, and it gave specific instructions to come to this location.

But when wasn't the safety of the entire human race at stake? Ever since the Titans mysteriously appeared many years ago, humanity had been on the verge of extinction. If not for the protections of Walls Maria, Rose, and Sina, the Titans would have devoured them all long ago.

Yet a letter such as this could not be ignored, especially since it had the royal seal on it. That meant that it came from those at the very top. But the former commander of the Scout Regiment, Erwin Smith, and the leader of the Special Operations Squad, Levi Ackerman, knew to be cautious. There were conspirators in the government, and many people would love to see them dead.

While most of the residents had grown content with being sealed off from the outside world, putting their faith in the giant structures that protected their society from the Titan threat for over 100 years, that had changed when the mysterious 60 meter tall Colossal Titan and the seemingly indestructible Armored Titan appeared and broke through Wall Maria, followed by Wall Rose just a few years later. Had it not been for Eren Yeager sealing up the breach with his, as of now, unexplainable ability to transform into a Titan, humanity would have surely perished.

Of course, having a human that could turn into a Titan by simply injuring himself, Eren's preferred method being to bite his hand, caused a great deal of concern to the public and the higher ups. Therefore, Eren was to be monitored at all times, even put down if necessary, and it was for this reason that he had joined the two leaders.

None of them had been to his part of the city, let alone in this building. In truth, they hadn't even known it was here at all, not having cared for much of anything beyond killing Titans. And they weren't foolish enough to come to an isolated area alone where they could be ambushed. Just outside, a few trusted and highly skilled members of the Scout Regiment stood at the ready. Mikasa Ackerman, foster brother of Eren, and the best there was at killing Titans after Levi. Armin Arlert, brilliant strategist and fearsomely loyal soldier. Jean Kirschstein, cynical, natural born leader with great assessment skills. And Hange Zoë, 14th commander of the Survey Corps, obsessively passionate about discovering everything there was to know about Titans.

Knowing who to trust was a difficult thing these days. It was hard to figure out who the enemy was, made all the more difficult with the appearance of the only Female Titan ever seen, who, in fact, turned out to be a Titan Shifter like Eren. Discovering that it was Annie Leonhart, a trusted friend and mentor, had shaken up all those that had been close to her. It also posed a horrifying question, how many Titan Shifters were hidden among them? Asking Annie was not an option, for she had crystalized herself to prevent being interrogated.

If you couldn't trust your friends and allies, how could you even consider trusting strangers? This Dr. P was a stranger for sure, yet the urgency of the letter required action on their part. At the very least, it needed to be looked into, and so, here they were.

After having been granted access to the facility, the three had been asked to wait in what seemed to serve as a lobby. They didn't have to wait long, an elderly bald man with glasses and a long white beard, wearing a white lab coat, came out to greet them. As first impressions went, he came across as friendly enough, but under the watchful gaze of the highly skillful Erwin and Levi, there was an air of anxiety about him.

"Commander Erwin, Captain Levi, how wonderful to meet you. Thank you for answering my letter and coming on such short notice. I am Dr. Pacu." His gaze landed on Eren, and he cleared his throat. "I believe I requested for the two of you to come alone."

Erwin lifted his chin higher before replying. "Eren Yeager is to be watched at all times."

"And with recent events," Levi added, "we had to be wary of walking into a trap."

The doctor hesitated. Sighing, he reached into his pocket and pulled out a picture. "Very well. Lets get straight to business. This is the reason why I asked you to come here."

He passed the picture to Erwin, and the three studied the image. It was the picture of a Titan. It had an average body build for a Titan, perhaps somewhat more muscular than normal, with long spiky blonde hair that fell down its back, nearly reaching its waist. As was typical for a Titan, it lacked genitals, though it still appeared to be male. Its arms were well built, but were blood red, lacking skin from the top of its shoulders to the end of its fingertips, much like the Colossal Titan.

At first it appeared as if it was wearing jewelry on its hands, but upon closer inspection, they saw that these jewels were in fact spikes; four on each hand, protruding from the knuckles, each one about the same size as the Titan's fingertips, and they seemed to be made out of the same hard crystal-like substance the Female Titan's skin hardened into.

The rest of its body was covered in skin, as was the norm, though like with all Titans, it seemed to be semi-transparent, allowing the blood flowing beneath it to be distinctively made out. Its mouth had a unique deformity that greatly resembled Eren's in his Titan form, only the teeth were sharp and pointy. And judging by the trees in the background, they could estimate that this Titan was in the 13-15 meter range.

Eren glanced at the doctor. "So what? It's just an another Titan."

Dr. Pacu adjusted his glasses. "Not quite, young man. This ones an abnormal."

They knew what that meant. Titans that were labeled as 'abnormals', or 'deviants', behaved differently than others; be it their actions, the way they moved, or some other distinct behavior that separated them from normal Titans. Though they were rare, these kind, with their erratic and unpredictable behavior, faster speed, and unusual way they moved, made them even more dangerous than the average Titan.

Levi seemed unimpressed by this. "I don't see what this has to do with us, or why it's so urgent. Abnormals appear every now and then."

The doctor shook his head. "Not like this one; you can be sure of that. This one is different from every other Titan we've seen before, much like the Colossal, Armored, and Female Titan. Not to mention our young friend here." His eyes went back to Eren. "That's why we took an interest in it."

Erwin eyed him suspiciously. "What do you mean we? Who are you anyway? And what is this place?"

Dr. Pacu held his head up high proudly. "We are his majesty's royal science, research, and development team. Here, at our base of operations, we dedicate ourselves to making the world a better place by finding ways to deal with the Titan scum. Even past members of our team assisted Angel Aaltonen in the creation of the Three Dimensional Maneuver Gear you use to fight the Titans."

Levi raised an eyebrow, now looking interested. "And why have you taken such an interest in this Titan?"

A dark look crossed the doctor's face. "I'm afraid that's classified. Just know that at the time of its discovery, it seemed that Titan X would be a valuable asset to our research."

Eren's eyes narrowed. "Titan X?" Was that the thing's name? He didn't like giving Titans names or labels, like they were anything even remotely human, no matter how much they resembled them. The worms in the dirt were more worthy of life than those vicious man-eaters, and they didn't give names to them beyond what their ancestors identified the different species as, strictly for research purposes.

Erwin didn't care about such trivial things, and his irritation was beginning to rise over the situation. "And I assume you would like for us to capture this Titan for you, am I right?" That would be just like those snobbish higher up, getting him and his men, good soldiers, to risk life and limb for their own personal gain. Capturing a Titan was extremely difficult, made more difficult the larger they were. Catching an abnormal was damn near impossible. And now they were expected to capture this Titan X while the doctor sat safely behind the walls?

But Dr. Pacu surprised them all with his answer. "No, sir, I want you to kill it."

Even the usual stoic look on Levi's face revealed that he too was surprised. "Kill it?"

Dr. Pacu nodded. "It has been decided by my team and I that this particular Titan is far too dangerous to be left alive. It must be put down at all costs, otherwise all of humanity is doomed."

Suspicion arose in the three soldiers. How could a single Titan wipe out all of humanity? It was true that even a single Titan was incredibly dangerous, but even civilians could kill one lone Titan by overwhelming it with cannon fire. Granted, that alone could prove to be difficult with their rapid regeneration abilities, the only way to kill a Titan being to carve out a chunk of flesh large enough and deep enough from the back of the neck, severing the main nerve that spread through the entire body, thus killing it before it could regenerate.

"What is it, exactly, that makes this Titan so dangerous?" Erwin asked, though he suspected he knew what the doctor's reply would be.

And he was right. "It's classified. Trust me when I say that there are some things you are better off not knowing. You'll sleep better at night remaining ignorant."

That was unlikely. The nightmares the Titans caused were unimaginable. Ranging anywhere from three to fifteen meters tall, excluding the 60 meter Colossal Titan, and the recently discovered Hidden Titan in Wall Rose, they were practically mindless, emotionless, violent monsters. Their need to eat humans actually seemed to be unnecessary since they got all the energy they needed from the sun alone. After all, they had supposedly lasted over 100 years without any sustenance. Eating humans seemed to be a highly enjoyable act for them, nothing more. Each one with either a big smile or a blank expression on heir face, they were made all the more eerie by the fact that they looked remarkably similar to humans.

Erwin and Levi looked back at the picture, thinking things through. Eren was ready to obey whatever order they gave him. He didn't care if they went after this particular Titan or not, just as long as he got to kill some of them.

A look passed between the commander and the captain, an unspoken decision seemingly reached. "Very well," said Erwin, "we'll take care of your Titan X. Although the odds of actually finding it among all the others is very slim, we'll be sure to keep an eye out for it during our scouting missions, and go after it if it's seen."

Dr. Pacu pushed his glasses farther up his nose; it seemed they slipped down a lot. "I'm afraid that won't be good enough. We can't wait around for you to randomly run into this Titan. I need you to seek it out and put it down as soon as possible."

Levi's eyes narrowed. "With all due respect," he muttered, his voice dripping with sarcasm, "how exactly do you expect us to find a single solitary Titan out of the millions that are out there?"

In answer, the doctor snapped his fingers. The double-doors behind him opened, and a woman also wearing a white lab coat entered the lobby, apparently having been waiting for Dr. Pacu's signal. She handed him a fancy metal box and hurried back through the doors. In turn, the doctor then handed the box to Levi, who looked at it curiously.

"What's this thing?"

Dr. Pacu merely pressed a red button on the box, and the glass screen lit up. A few seconds passed, and an image appeared on the screen. At the bottom, there was a small white dot, sending out what appeared to be waves across the screen. Aside from some numbers along the right side of the screen, it was a blurry green image, the only other thing standing out being a second dot in the top left corner that seemed to pulse whenever a wave the white dot sent out passed over it.

Eren's eyes were as wide as saucers as he looked at the strange metal box. "Whoa, what is that?"

Looking proud of himself, the doctor patted the box. "That is some technology from the old world, from before the Titans showed up. As part of our research, we aim to rebuild and repair the ancient technology our ancestors used. None of it has been released to the public yet, but our team has actually come a long way. This device that you see before you is our reconstructed version of what our ancestors called a radar."

He pointed to the red dot. "That is Titan X. We inserted another piece of ancient technology inside it. It's called a tracking device, and it goes along with the radar. Together, these two devices were used by the people of the old world to find anyone or anything, no matter where it went."

"That's amazing!" Eren exclaimed. He had always been fascinated with the old world and what lay beyond the walls; almost as much as Armin, who would love to see this strange device.

The doctor chuckled. "If you think that's amazing, just watch this."

He pressed another button on the metal box, and the numbers on the sides changed as the screen seemed to zoom in. Pressing another button beneath it caused the screen to zoom out once more.

"These buttons control the range. See the numbers on the sides of the screen here. They tell you the distance. This," he pointed to the white dot, "is where we are. Or, more specifically, where the radar is. Use this to find out where Titan X is and how far away from it you are."

Erwin was impressed; even Levi silently admitted that this was rather amazing, but something the doctor said made him curious. "You say it tracks Titan X because of the device you inserted in it. How exactly did you manage to stick something inside a Titan?"

He received a glare from the doctor at the question. "Not that it's any of your business, but it was done while it was subdued."

"And who subdued it. As far as we know, any captured Titans were overseen by Commander Hange Zoë."

Dr. Pacu humphed. "In case you've forgotten, the Scout Regiment is not the only group dedicated to fighting Titans. We have a few soldiers of our own in employment."

Erwin raised an eyebrow in interest. There were soldiers that worked for the doctor? This was certainly news to him, but he did know that inquiring about that right now would be a wasted effort based on how careful the doctor was being with his use of words. He decided to store that information away for later.

"So," he said, deliberately changing the topic. "This radar, how does it work?"

Levi glanced at him, noting how he had changed the topic, but said nothing of it as they waited for an answer. A few seconds passed where Dr. Pacu hesitated, seeming to consider whether he should tell them or not. "I guess there's no harm in you knowing. In the old world, we had these things called satellites. Our ancestors sent them up into space. Down here, we had various forms of technology that could make contact with them, and they would send back information on anything they picked up, or so our research leads us to believe."

Eren unconsciously looked up at the ceiling. Sending objects into space? Was that even possible? They couldn't even go out beyond the Walls without risking being eaten, so the possibility of going up into space was incomprehensible.

"The tracking device we inserted inside Titan X connects to one of these satellites," Dr. Pacu continued. "The satellite we managed to gain access to is able to read the signals the tracking device gives off, and send the information to the radar here. We can track Titan X wherever he is."

While Eren was busy marveling at this amazing ingenuity, Erwin and Levi were busy calculating what the doctor had told them, and it brought forth an abundance of questions. How had the doctor and his team discovered this Titan, and why had none of them ever heard of it before? How did he manage to insert the tracking device thing into the Titan's body? It seemed to imply that, at one point, Titan X had once been in the possession of Dr. Pacu and his team. If so, how had they captured it, how did it escape, and where had they been keeping it? In this facility? It was located in an isolated part of the inside of Wall Rose, so it was a possibility.

There was also the question of what was so important about this Titan that the doctor and his team had saw fit to spend so much time and money on it with reconstructed technology from the old world. How could a Titan possibly be worth all that trouble, and why did they want to suddenly throw it all away by killing it? There were far too many questions.

Something wasn't right. There was a lot more to this than Dr. Pacu was telling them. But one thing was for sure, whatever the doctor and his team had been doing, they considered this Titan to be more dangerous than the importance of whatever research they were doing. If they were indeed ready to throw away all their research just to kill of this one specific Titan, then they were right about it needing to be put down before whatever was so dangerous about it came to pass. They could find out whatever the doctor was hiding once the threat had been neutralized.

"You can count on us," Erwin assured Dr. Pacu. "We'll find this Titan, and we'll put it down."

The relief on Dr. Pacu's face was evident. "Thank you, thank you. You're doing a great service to your fellow man. There's just one more thing." His gaze shifted to the unwelcomed third party member. "Eren Yeager is not, under any circumstances, to accompany you on this mission."

The three soldiers were surprised. Levi hid it well, and Erwin's eyebrows merely rose, but Eren was openly outraged. "What? Why? There's no way I'm staying behind! I'll take this Titan out in no time flat."

Erwin held up his hand to silence him, and looked at Dr. Pacu. "Doctor, understand that Eren is a valuable asset to the Scout Regiment. With him aiding us, our chances of defeating this Titan are several times greater."

The doctor pushed his glasses farther up his nose. "Be that as it may, he must remain behind for this mission. To have him and Titan X meet will be a great folly."

"Why?" Eren demanded. "What's so bad about us meeting?" His eyes narrowed. "Or is it classified?"

Dr. Pacu glared at him. "Indeed it is. I told you that there are things you are better off not knowing. This is one of them. I will not negotiate on this. Eren Yeager is to remain behind. Or should I put my faith in the Military Police instead?"

Eren scowled. And even though Erwin and Levi were better at keeping emotions in check, he knew that they greatly disapproved as well. Rivals was too mild a word to describe the relationship between the Military Police and the Scout Regiment. The Military Police was completely corrupt. Not a single person in the Scout Regiment trusted them. The doctor knew this, and was more or less giving them an ultimatum. The thought of the Military Police taking charge of something that was seemingly this important did not sit well with them.

Erwin sighed. "Very well, Eren Yeager shall remain behind."

Eren opened his mouth to protest, but a look from Levi silenced him.

Dr. Pacu gave the commander a suspicious look. "This is very important, even though I can't tell you why. Do I have your word?"

Erwin stood up straight and placed his fist over his heart in a standard military solute. "On my honor as an officer, I give you my word." His eyes narrowed. "However, you should keep in mind that it is you who is asking us for a favor. You may want to work on how you ask for favors in the future."

The doctor just smiled and turned to leave. "Thank you, I'll keep that in mind."

Eren's fists clenched. He had a feeling that they had just made a very big mistake.

(A/N: Geez, Dr. Pacu certainly didn't give them much to go on. But don't think that Erwin and Levi are just blindly following orders. They're plenty suspicious fully intend to find out more about this later. It's obvious the doctor is hiding something. But what is it? And just what is this mysterious Titan X? What could possibly make it so dangerous? You'll have to wait and see. In the mean time, I would love to hear from you guys. Does anyone have any ideas about what makes this Titan so dangerous? I'm interest in your theories. I already told one of my readers what it is, you know who you are, so please reframe from spoiling it for others. I'd still love a review though. Over and out.)