It all began more than 20 years ago when the Savages, unknown alien monsters descended to Earth and indiscriminately attacked the human race. Their reason for attacking mankind was unknown, but they were a formidable foe. Conventional weapons were ineffective against the creatures, so humanity was forced to look into new developments to prevent annihilation.

The first was the introduction of the Hundreds, made shortly after the Savages' arrival and their successful attempts to destroy them despite being outclassed. Made of power crystals currently unknown to man, they evolved into powered suits that were highly effective against the Savages. As production of these weapons increased, so did the diversity and demand to train their wielders identified as Slayers. Thus, began the creation of warships such as the Little Garden, where Slayers were organized and assigned specifically to counter the enemy Savages.

Not so long after the Hundred became a standard weapon, another that rivaled and even exceeded its power was introduced. Whether by its ditzy creator or the absurd concept, there was widespread disbelief in its power. All that was disproven when all of a sudden, the world's missile arsenal was hurled straight towards the islands of Japan, now named the Empire of Yamato. The unit personally dispatched all the missiles with not single one hitting the island cluster.

The pilot of this powerful weapon identified itself as the Infinite Stratos, only known as the "White Knight," claimed no allegiance to anybody. In response, the world sent their forces including the new Hundreds to obtain this new weapon. Aircraft, naval warships, military satellites, and even Hundreds were deployed to capture this unknown weapon. The latter weapons proved to be much better like they did the Savages, but it still wasn't enough to accomplish their objectives. But the most unexpected part was that despite losing so many machines, there were no human casualties.

Eventually, this forced the dramatic changes that swept across the globe. Knowing the full power of the IS, the Alaska Treaty was enacted, which shared the limited IS technology to all the world's nations to prevent one from dominating another. It was within that same treaty that IS units would not be part of any armed conflict as the Hundreds were, the only exception being dangerous threats like the Savages.

Since the introduction of the Infinite Stratos, it became a known fact that only women were capable of using these weapons. With the balance of power broken, women dominated men in society. Besides this and the threat of the Savage, warfare shifted from the battlefield into politics and combat arenas. The world seemed to enter lasting yet tense peace.

And then, even that changed four years ago.

It all started in during a political rally in New York when out of nowhere, a strange suit appeared, neither a Hundred nor IS due to the changes in deployment and generation of unknown particles of various colors. The unknown weapon killed the politician and his audience during his speech and proceeded to destroy the city's financial district. A simultaneous attack from a similar weapon occurred at peace conference in Beijing, China, which killed the nation's leadership and trashed the nearby military forces. Another attack on the same day hit Switzerland, which held Russian leaders and dignitaries.

Wave by wave, their attacks continued. Whether they were military, civilian, economic, or political, all were targets of these powerful machines. It was only a month later, did international response occur with massive military power. Unlike any precedent before, even with the Hundreds and IS units, their efforts were futile against their combined power. A short-lived resistance against machines followed with a final stand in Eastern Australia before the entire world was in disorder.

But what were these machines and who piloted them? What was their main objective out of all of this? Even four years after the attacks began, no one knew. Witnesses were few and information was limited, but the units were confirmed to be called "Scythes." Due to the destruction they caused and the turmoil that resulted from it, they became known to the public as "Death Scythes."

Since then, humanity is still under a dark shadow. Savages continued to attack, the Death Scythes were still at large, and despite following the Alaska Treaty to restrict the use of IS units, the various nations continued to fend for themselves. The world's most dangerous weapons gave rise to mass-produced machines that futilely attempted to replicate their power. Warfare has dominated Earth, and the constantly present threats prevented anyone from changing it.

That is...until a certain incident occurred...where the world was about to change once again.

A young boy within 14 years of age with black hair was sitting on his bed within a dimly lit room. The only source of light was the projected image on the other side of wall showing a 3D images of the Earth with a space background and many satellite icons surrounding it. Several images marked locations of various events happening across the globe.

Yuuki Kamikaze was observing all of the wars happening. All of them were about humans fighting each other despite the presence of more dangerous threats like the alien Savages. While he looked emotionless, inside himself were overwhelming feelings of anger and sorrow over the pointless fighting and destruction. But it was a means for playing catch-up on world events and why he was in that room.

Just a while ago, the renamed People's Unified Republic of Korea spent its years launching a war campaign against its southern neighbor. Thanks to the Death Scythe attacks, the northern nation crossed the DMZ line to attack the helpless South Korea that took the brunt of the damage. Despite losing their home capital of Seoul and having the whole Peninsula wither blockaded or neglected by the rest of the world, the South and its remaining allies strived to keep the totalitarian forces at bay.

Then he came up. No one could've expected that he would be the one to turn everything around. He never used his real name at the time; the records state his name as Kim Ki, a Korean name of which he chose himself, who attended high school in Daegu. Although it suffered attacks from insurgents and tightened security to a high level, it was one of the remaining free cities not under the North's control and allowed its students to live as normal lives as possible.

One of those insurgencies gave him something no one thought was ever possible, a Scythe that exceeded the other mass-produced models but not part of the known nine Death Scythes. With that weapon, he managed not just to decimate the North's army, but unintendedly wipe out its political and military leadership as well. PUROK's reign of terror disappeared in an instant, which should've been something worth celebrating.

However, the end of the PUROK's threat that lasted for more than a century didn't stop for it brought unintended guests into the fray, the Death Scythes, the same machines which triggered the war in the first place. He was only lucky to survive their attacks despite his lack of experience and that was only by making it look like he was utterly annihilated.

His only rescuers were members of UN-EOS, the only international power that lives and operates in space. The two had common interests between one another, yet he felt like he didn't belong until his near-death incident. When it became clear he could not kepping having an ordinary school life, he took the second best option, to work with the group so that he can live that life again. And to do that, both wars and the Death Scythe machines that started them had to go away.

An alert went off in the top right corner of the screen. Seeing the signal, Yuuki checked his military uniform, which was primarily black with a blue pair of cuffs and collar. The single white stripe and star marked his rack as Ensign thanks to his power and role on the field. Although etiquette wasn't a concern due to his civilian background and nature, he found it best to look presentable before his superiors.

The map was replaced with an enlarged image of a flag. It was a blue background with four white stars on the top and bottom. At the center was a large white dot with two rings of the same color, each with a dot that aligned upward with the center. The dot on the inner ring was tiny while the one on the outer ring had a size in between. Below the symbol showed "UN * EOS" in white letters.

As the "flag" of the organization faded out, the boy's commanding officer appeared before him by her office desk. She wore a blue uniform fit for military officers, complete with three stripes and star on the sleeves and a silver leaf bade by her breast, indicating her rank as a Commander. She had some smooth, dark red hair coming out of her blue beret, though her emerald eyes were more than visible to Yuuki's eyes.

"It's you," Yuuki unconsciously said before straightening himself. "I'm mean, reporting, ma'am."

"At ease," the Commander spoke in a professional voice. "I see that you've been catching up on the latest news. More reports on the warzones again?"

"Yes, ma'am...I-I mean, Commander."

"I know this is tough for you, but don't overburden yourself. The missions will require sharp focus despite your weapons and its technology. We can not allow you to sleep on a job or have another incident just like back in Korea."

"Sorry."

"Don't be, for all missions will be postponed for the future."

"Ma'am...I mean, Commander?"

"The UN-EOS Board of Directors have just given us new orders. Perhaps, it's because we only have you who can fight the Death Scythes and with the additional threat from the Savages, they demand more firepower against the enemy."

"I see...so where'll we be heading?"

"No one will be heading anywhere except your team. You'll remain assigned here in the Empire of Yamato for future operations. Will this be a problem for you?"

"No. But forgive me for not being clear. Where exactly will I be staying?"

"That's where things get complicated," the Commander put it lightly. "To start, despite being sheltered in Korea for a few years, I assume you're familiar with the Infinite Stratos?"

"Yes, they're the so-called 'world's most advanced weapons.' Supposedly, they were going to replace the old Hundred units...until those 'things' arrived."

"That's correct. You'll be attending the main academy for IS users on Yamato's artificial island. When not conducting operations, you'll be staying at the school for study and combat practice."

"The Academy…"

"Do have a problem with this?"

"N-No, Commander, the thing is..."

"I know what you're thinking, and do not be alarmed. You're not going to be alone. Take a look."

The Commander then displayed a series of news images and videos for Yuuki to see. Each of the headlines showed another student about Yuuki's age. He even had the same raven-colored hair, although it was significantly shorter compared to Yuuki's. The boy was that famous child was all that pleased when his photos were taken and even tried to run. Considering what he knew about the IS, it wouldn't come to a surprise that he'd be freaked out.

"Ichika Orimura," Yuuki muttered as he read the headlines. "The first male to operate an IS…"

"These reports were over a week ago. If what you and your comrades say are true, it happened just after you found that machine. The Board of Directors and I doubt that these two incidents are related, but they have intrigued them nonetheless."

"But-"

"The Board has already planned to cover your true status so that you won't be piloting your actual Scythe. But the Academy still requires a nation for you to represent."

"You want me to represent Korea."

"When the Death Scythes attacked Seoul four years ago, they completely wiped out its I.S. program and all of their representatives. Until now, the Academy had no more reason to get involved, especially with all the other nations being more concerned about their personal problems and interests. I know this isn't the ideal situation, but you'll have to use your original Korean name once more for this operation."

"I...understand. It can't be helped."

"Tomorrow, you'll speak to Warrant Officer Ciero about the changes to the Zero Scythe. For now, you should rest for tonight, for you'll have some big days ahead of you."

"I understand, Commander."

"By the way, I mentioned before you do not have to merely call me Commander. You may be an officer, but you're still not fit for a soldier. Until then, you can just call me Ms. Straus for now."

"Y-Yes, Commander Straus."

"Take care."

After giving a rare smile to the boy, the woman cut communications, returning to the UN-EOS flag. After a few moments, she got up from her seat and kicked up enough force to glide over to a window on the right.

Commander Willow Straus gazed upon the Earth within the Kitty Hawk, a UN-EOS Classified Military Satellite that few people even in the organization knew. All of the furniture was attached to the floor. Although there are some objects stuck on top, objects such as books on the shelves had to be sealed tightly behind glass doors to keep gravity from letting them loose.

Upon reaching the window, Commander Straus gazed upon the Earth and the space background.

Space...long before it became a reality, setting objects, let alone living quarters was a dream sought by many. Whether it was for its natural wonders, vast resources, or unimaginable potential, almost everyone believed it would solve all of humanity's problems. They still ran into many obstacles and in the end, their ignorance left those same problems unsolved within their wake.

The UN-EOS Commander had no interest in solving all the global issues of the world. It wasn't because they were constant issues that will never be solved even in space. She was a soldier; someone made to fight. Thus, politics were never part of her job description.

Despite that, there was still the boy who'd pilot their greatest weapon. He was not a soldier, but a civilian pulled into an unexpected circumstance, now wielding the best weapon against the scourges of humanity. With that in mind, she wasn't sure whether he should be fortunate or unfortunate over his situation.

Taking a brief sigh, she returned to her desk and tapped buttons onto the screen. The screen in front then changed to that of a phone screen, displaying its progress in calling a certain person. Below it labeled "IS Academy: Chifuyu Orimura."

Inside a room that resembled a command bridge for a warship or a control tower for an airport. The sun was about to set after another day at the I.S. Academy, and the stars were becoming visible. Only two women were present within the room.

"So how is Orimura doing, Orimura sensei?" the bi-speckled woman with green hair just walked by with a glass of hot coffee on a tray. She was approaching the second woman looking through the window that showed the island's surrounding waters and lands on the horizon. The other woman named Orimura was wearing a typical black business suit, high heels, and stockings. She had long black hair tied into a thin ponytail that went down to her waist. Her arms were crossed before she took the glass of coffee.

"As you expect," Chifuyu Orimura responded as she took a sip. "This is his first day, so he has much to learn compared to the other students."

"Do you think it was a good idea to pair him up with Shinonono?"

"As if I'd let him share a room with a complete stranger. Besides, Shinonono was his childhood friend from long ago, so she knows him better than any student at this school. Other than her, being the only male at an all-girls school would surely make him nervous."

"You really do care about your brother, don't you?"

"Got a problem with that?" Chifuyu startled the bi-speckled teacher by turning her usual stern gaze towards her.

"W-Well, I…"

Their short conversation was interrupted when a ringing noise came from Chifuyu's pocket. She placed her glass back on Maya's tray. As the green-haired teacher left for the other desks, Chifuyu took her phone out to answer the incoming call.

"This is Orimura."

"It's been a long time."

The voice of Commander Straus came on the line. The sudden voice caused Orimura herself to be startled, followed by a glare against her phone.

"What do you want?"

"Orders just came the Board of Directors. They're looking for your cooperation."

"If they want me to join the organization, then tell them that I-"

"They're not looking for you anymore, Ms. Orimura," Straus spoke in an informal manner. "They already have what they need. Something you may haven't heard of until recently."

"And what would that be?"

"A Scythe that could compete against the Death Scythes."

While the name was never given, the description caused one of Chifuyu's eyes to widen for the moment. A glare from her eyes then followed that.

"Are you certain?"

"There's no doubt about it. They found the actual Scythe the other Death Scythes were based on. Now, we have a chance to end this, though the given pilot is...inexperienced."

Chifuyu paused for a moment before letting out a heavy sigh.

"For now, I need you and the other teachers to create a student profile for the pilot. Considering you already have him at the school, it shouldn't be a problem enrolling this one as well."

"Another male at school?"

"Will that be a problem?"

"No," Chifuyu assured as she looked down from the window. She was sure that she saw a raven-haired boy walking outside the Academy, of whom she knew very well. "In fact, it'll be more of a benefit, as long as nothing goes wrong."

"Very well, I'll send the information soon."

The phone call ended, and Chifuyu placed her phone back into her pocket. She let out another heavy sigh, still gazing at the Orimura sibling who was wandering around the school. To say that nothing can go wrong was a blatant understatement since her experience proved that anything could go wrong. How much they wrong, well...that was up to debate.

It was the next day at the UN-EOS ground base established in Yamato; its location in Kyushuu was also kept to the world. Yuuki entered through a metallic door leading to an armory. Usually, he would turn to see his Scythe, the weapon that saved his life and brought him to this facility.

Yuuki had limited knowledge about this weapon, also known as the Zero Scythe, which she only knew from experience and what the head researcher told him. It was bigger than a normal human but only less than a meter larger than a normal human. The stilts on the machine could be adjusted for the height of teenagers and adults alike. Cuffs on the arms and legs held the pilot tightly onto the machine. Three bars were by the waist; two would wrap around like a belt, and the third came from underneath the pilot's legs, all connecting to a glowing buckle shaped like an upside-down house symbol. The frame itself looked skeletal, especially by the legs and arms, but had many hardpoints that potentially could all sort of useful and powerful equipment. The only weapon it currently had was a single-edged sword stored in a scabbard on the left hip. The helmet that closed down upon his head would display vast amounts of information in real time. While that only covered the top of his head, that and his metallic gray latex suit should be enough to conceal his identity should any get a close look at his face.

Yuuki noticed that the frame lacked the sword and its most important part. That's when he turned to see a man with long white hair holding it in his hands, a robotic spinal cord with a neon blue-green sphere at the bottom surrounded by swirling particles of corresponding colors. That was the shape of the Scythian Drive, the heart, and mind of a true Scythe.

The man holding it was Adam Ciero, his age between twenty and thirty years old. He was a Head Researcher, both as a title in UN-EOS and as part of a claimed organization with the said name. Of all members in the space organization, only he, one of the newest members with the rank of Warrant Officer, had the most knowledge of the machine. Yuuki could see that as he was dressed up in his white lab coat and black pants, carefully holding the Drive into a more humanoid frame.

Noticing how he was doing delicate work, Yuuki waited for Adam to finish inserting the Drive into the new machine before calling out to him. But before he could, the Head Researcher already spoke first.

"Impressive, isn't it?" Adam said, aware of Yuuki's presence. He turned around to show his smooth face, displaying a gentle smile to the boy. "When it comes to switching between two machines, it's a challenge. But once you have actually done it, there's a sense of accomplishment."

"What is this?" Yuuki explored the inside of the smooth, more humanoid shape of the dark metallic frame. The chest and horned helmet were open, showing the hollow inside of the machine aside from the Drive.

"This will be your 'Infinite Stratos' when you attend the IS Academy as of today. It should work like the Zero Scythe, expect it incorporates elements to make it work like an Infinite Stratos. And here's another thing."

Adam displayed on a screen a visual of two overlapping shapes ironically representing a man and an Uchigane unit. The Uchigane then vanished into a pendant hanging around the neck.

"The Infinite Stratos has a compact form when not in use. Since you'll be carrying your 'IS' around with you, that presents a problem, of which I already came with a solution. Touch the unit and see for yourself," Adam said as Yuuki complied. "Now put your mind into it."

At first, it didn't make sense to Yuuki, putting his mind into the machine. However, the alien nature of the advanced units showed there had to be a special trick. A blue-green light then enveloped the new frame for the Zero Scythe. The bright flash forced Yuuki and Adam to close their eyes until it faded away.

When Yuuki came to, the Zero Scythe's frame was gone. Instead, he found a dark metal chain with a spherical, blue-green gem hanging from his neck.

"That will be your Zero Scythe converted similarly to the IS units' Standby Mode. If you want to restore, just focus on your mind like you just did. However, you should attend the Academy and learn how it's operated before you go on trying to use it."

"I understand."

"The Head Researchers have taken note of the Death Scythes' capabilities in addition to the Zero's and IS units. Apparently, they have a similar method called a "Seal," which allows them to conceal their units or transform them into a more compact form. That's why during some of their strikes, they managed to hit their targets without warning. It's not the same, but with Nano-Scythes, it can imitate the process to a close second."

"Nano-Scythes?" Yuuki only heard of the term, given to nano-machines that worked with one of the Death Scythes' units. But that Death Scythe was the only known unit capable of wielding and producing such machines.

"The Head Researchers learned a lot from both types of machines," Adam answered. "Some of our recent compatriots came from IS companies who secretly worked with us. Thanks to them, we managed to replicate some of Death Scythes' weapons and abilities we thought would take years to reproduce. In that regard, the creation of the Infinite Stratos was indeed a miracle."

Yuuki wasn't exactly sure he would agree. Without a doubt, the Infinite Stratos showed advanced capabilities that could never be defeated with conventional weapons. At the same time, however, he heard even they couldn't fight off the Death Scythes despite their great advantage in performance and outnumbering them more than fifty-to-one. That said, he wanted to prevent a disaster from occurring and went to restore the unit back on the table.

"Mr. Ciero," Yuuki assertively asked as he placed the unit went back on the table. "If you can, I want you strict the power on this unit as much as possible."

"Well, of course, Yuuki. We do not want the whole IS Academy to know you pilot a vehicle that rivals the Death Scythes. Besides backlash, you'd be in a lot of trouble with the girls."

"Thank you."

Yuuki didn't reply to his comment as if wasn't a bother for him. The other soldiers said that he was closed off until he became pilot of the Zero Scythe. There was no telling what was going on in his mind. It should instead be seen as a symbol of luck for everyone else in UN-EOS' 4th Security was either female, already married in Adam's case, or had their eyes set on someone else. Even so, the Head Researcher couldn't help but wonder things would be like at this school.

Only time could tell.

Although the story would follow up on Infinite Stratos, it's ultimately a crossover with Hundred and an original work I've conjured up in the past few months.

Death Scythe is my response to Infinite Stratos and similar series. The main story takes place on Earth, four years after the mentioned attacks that crippled the world's infrastructure, which gave birth to weapons called Scythes. The name refers to any weapon with mechanical limbs such as spider tanks, bipedal walkers, automatons, transforming robots, powered armor, etc. Despite being way outperformed by the original Death Scythes, they still dominate the industry as the mainstream hardware in the resulting war racket. The DSs responsible are still at large, and no nation has attempted to find them since they're too busy fending for themselves.

That is until the appearance of Yuuki Kamikaze, the main hero of the story. This crossover takes place after the first two planned books, but Yuuki spent that time in the last free states of South Korea. Out of a coincidence, he discovered a Scythe that didn't belong to the Death Scythes and unintentionally used it to depose the aggressive northern regime, ending the war that went on all those years. This global phenomenon consequently attracted the Death Scythes and brought him into the international UN-EOS organization that sheltered him.

And now, in this fic, he's enrolled into the IS Academy. Where this goes, that's for when I get to further into the story.