I do not own Ben 10 or Fate/Stay Night. Those both belong to their respective creators and not me. I'm only writing this because the idea wouldn't leave my head and posting it because I think my readers would enjoy it. So, to everyone who is reading this, enjoy!

Fate/Stay Night: Ultimate Master

By Ten-Faced Paladin

Night 1: Arrival and Avenger

(Oo/0\oO)

The airport was busy and somewhat crowded as airline commuters went to and from all of the main entrances. The day was pleasant enough, but for all of the natural lighting the windows provided in the airport, it certainly didn't make waiting in line any easier. Some people were made particularly grouchy about the fact it was such a nice day outside and they were trapped in bureaucracy. Case in point and one of the main players in the game to come was a young western boy of sixteen who wore a green jacket, jeans, and had brown hair. He also had a satchel hung over his shoulder and a suitcase in his hand.

"Sometimes I hate my job," the boy sighed to himself, eyeing the surroundings.

His name was Ben Tennyson and he was in fact from an American city called Bellwood.

Ben used to be your average boy, but during a road trip with his grandfather when he was ten, he managed to gain access to a powerful alien machine known as the Omnitrix. With it, he was able to transform himself into ten different aliens before transforming into more as time went on. Being a ten year old, he used the Omnitrix for a number personal quests for fun and amusement, but he also used it to help a lot of people in need. As he grew up, Ben was forced to don the Omnitrix yet again at the age of fifteen to combat an alien race known as the Highbreed. A year ago, in a climactic battle against the warlord Vilgax caused Ben to lose the Omnitrix and eventually destroyed it. In its place, he managed to acquire the newest model known as the Ultimatrix. It was similar to the Omnitrix in that it transformed Ben into different aliens, but it had the added function of jumpstarting those aliens into evolved forms Ben dubbed as Ultimate Forms.

Recently though, Ben was allowed to take further part in intergalactic missions with the organization known as the Plumbers, officers who were charged with keeping the peace among the alien citizens of Earth and other planets. Unfortunately, a rather big fan of Ben's managed to discover his identity and in a fit of 'it-was-a-good-idea-at-the-time' revealed his name and face to the world. Ben became an instant celebrity, looked up to by numerous kids and teenagers, but mistrusted for his abilities by several adults, lead by reporter Will Harangue who seemed to make it his personal mission to send Ben down in flames and paint him as a menace to the people of America. Well, do that while making a quick buck on his book deals at the same time.

Ben's recent international flight was a result of his latest assignment from the Plumbers. He was sent out to Fuyuki City, Japan in order to investigate strange occurrences that seemed to be happening. Ten years ago, Fuyuki City was the source of a disturbingly large number of 'gas leaks' and 'accidents' that left many people dead, comatose, or injured with no idea as to just what the heck happened. The incidents were also coupled with large amounts of property damage in certain areas and strange energy readings which seemed to grow stronger and stronger until it peaked and Fuyuki City went up in flames. It was called the Great Fuyuki City Fire and it had a staggering amount of lost life in it, one of the highest records in the history of natural disasters. In recent days, the energy spikes were beginning to return and so the Plumbers decided to send in Ben so he could investigate. Since Ben was still being hounded by reporters and rabid fans, he was elected to be sent for the job since Japan was far enough away that no one may have heard of him. Well, that and he was one of their best junior agents next to Gwen and Kevin.

Speaking of the other members of Ben's team, they were ordered to stay in Bellwood until such a time that Ben needed backup or some other kind of emergency. Ben couldn't even be transported with the Rustbucket II, thus the reason why he was on a regular commercial flight rather than the incredibly fast space ship.

"I'll never complain about Kevin's speeding again," Ben muttered to himself as he finally got to the desk for arriving flyers.

Thanks to the latest in Plumber translation technology, Ben was able to understand what the clerk was saying to him. That in turn allowed Ben to be able to speak Japanese like a native, which surprised the clerk, but he didn't really comment on it. After getting his passport stamped and approved, Ben was finally free of the airport and allowed to enter Fuyuki City proper.

Fuyuki City itself was constructed a little oddly in Ben's eyes. The city itself was split in two by a river called the Miongawa which ran right through it. The two halves of the city were known as Shinto, which housed the urban side of the city while the other half was called Miyama, which had dibs on the suburban sections of the city. Miyama was then split into two further halves with the southern end holding more western-style homes while the northern section had more traditional Japanese homes. It was oddly organized for a city to Ben who had come from Bellwood where urban and suburban were spread out across the borders depending on who wanted what.

Stepping out into the sunlight, Ben shielded his eyes for a moment. He had half-feared that he was going to be mobbed by crazed fans like he had been on numerous occasions back in Bellwood. When no screams of adoration or calls from pushy reporters came, he felt a deep sigh of relief. It seemed that he would get the anonymity that he so craved these days, which was itself ironic since in his younger days he would have given almost anything to be a famous hero.

Hailing down a cab and telling the driver where he wanted to go, Ben sat back and slipped a file out of his bag so he could get a start on just what was going on. Inside of the file were a number of papers including readings about the incidents leading up to the Great Fuyuki Fire. A number of people who managed to survive ended up telling tales of people who were battling each other on an inhuman degree, using swords, shields, and even magic of all things. Most people wrote it off as hallucinations brought on by the 'gas leaks' and what effects they had on the minds of the people who inhaled it before it went up. What few officers that took it seriously were, managed to get descriptions of some of the people involved. Plumber technology which was only put to use recently because of events repeating managed to get high probability names to be connected to those names.

'Emiya Kiritsugu, Kotomine Kiriei, Tohsaka Tokiomi, Uryuu Ryuunosuke, Waver Velvet, Matou Kariya, Kayneth Archibald El-Melloi' Ben read over the names. They were the most probable names to go with the faces that seemed to come up most during the incidents that the police recorded and that the Plumbers managed to look into. However, there was some margin of error so it may all be wrong. Still, if he was going to talk to some of the people on the list, it was going to be tough. 'Emiya's dead thanks to a heart condition. According to data, Kotomine is the priest of the local Catholic Church so he'd be a good lead. Tohsaka's likewise dead, although he was murdered but any evidence was destroyed in the Great Fuyuki Fire. Uryuu's dead too, although evidence seemed to reveal he was a serial killer. Waver is out in England under a different name now and attempts to reach him haven't met with success. Matou died from failing health too. Lastly is that El-Melloi guy and he was shot and beheaded some time before the fire. Man, most of the people who would know what the deal was are dead! What the heck happened here?'

Of course, that list was only of the people who actually could be identified. Each of the people on the list was accompanied by someone who did the actual fighting while the others were supposedly nearby. Emiya was reportedly in the company of a blonde girl who wore blue and had silver armour on of all things. Tohsaka was said to be friends with a red-eyed man in gold armour who managed to cause his own share of damage before the fire. Uryuu was with a man in black robes and the strangest eyes one would ever see and Waver was accompanied by a red-haired man who was dressed like a Greek warrior. Matou was seen in the company of a man wearing black armour while El-Melloi was sometimes seen with a man in a black outfit who was carrying a spear. Again, no one took the reports seriously beyond checking to see if there was any evidence of such but with the fire, any possible evidence that could reveal the truth was destroyed and most people wrote it off as hallucinations anyway.

"We're here kid," the driver spoke up, snapping Ben out of his introspection. Looking out, he saw that he was at the hotel which the Plumbers had set up for him. It was a pretty neat place and normally someone of Ben's allowance would never have gotten in on a reservation. Luckily Ben was being paid as a Plumber and that reservations had been made by people who knew what they were doing when they assigned him this mission. It paid to have connections.

After a speedy registration, Ben caught an elevator up to one of the top floors before finding his room. Well…room was a bit of a general term. What he actually got was a very nice suite. It was tastefully decorated in a modern fashion and actually had three different rooms in it, perfect in case Ben needed to call Gwen and Kevin for reinforcements.

"Holy cow!" Ben gasped. "I don't even want to know what strings Grandpa pulled to get me this place." Quickly claiming a room, Ben came back out to inspect the rest of his temporary residence and that quickly became a tour of the kitchen. It was already stocked with foods and of all things a blender. Ben's eyes immediately lit up at the sight of the machine. Now he could make smoothies of any kind anytime he wanted! If it weren't for his assignment, he'd be sure that he was on vacation!

Ben was sorely tempted to go ahead and get a smorgasbord of smoothies ready for his enjoyment, but he managed to fight the urge. He was there to investigate weird events happening in Fuyuki, not gulping down smoothies until he would explode. Tearing himself away from the gorgeous sight of all of the potential smoothies, he returned to his room where his travel bags were kept before digging through his carry bag for what files he brought with him. Taking hold of them, he brought them back out. Bringing them to the living room, he spread them out so to get a look.

All of the files were a collection of information on the seven people who were implicated in weird events leading up to the fire. Some of it seemed complete enough for some, but others were sorely lacking. Emiya seemed like a simple enough guy. He married into a family of German aristocrats known as the Von Einzberns. It was a family which had a long lineage which seemed a little odd to allow a foreigner marry into them, but that was the stereotype since people could marry whoever they wanted. After the fire from ten years ago, he split off from his wife Irisviel (who apparently died in the fire or events leading up to it) and remained in Japan, not bothering to return to his in-laws. He died several years later.

Kayneth and Waver both came from England and had journeyed from their home country to Fuyuki for an unclear reason. Information on both of them was sparse at best. Kayneth was reported to be descendant of some minor noble family reportedly. Waver was a supposed child prodigy who was just as enigmatic as Kayneth and had even less on him, being a teenager at the time. The Plumbers were still looking into it, but for all intents and purposes the two were ghosts. Even Kayneth's body pulled a vanishing act after it was shipped back to England for burial and the only family member they knew of was his fiancée, although her body was found nearby with gunshots being the cause of death and her arm missing. Waver returned to England after the fire, but then practically vanished as well.

Uryuu was pretty much an open and shut case. The man was a total psychopath who was tied into several murders with his most heinous starting with a family he slaughtered by himself before several orphans in the city likewise went missing before being found dead in gruesome ways. When he was finally found, he had a bullet wound in his head. What was proposed was that he either killed himself out of his insanity for some reason or another, or someone took the law into their own hands and took him out.

Tohsaka, Matou, and Kotomine were all from Fuyuki and both Tohsaka and Matou both had long histories tied into the city. Tohsaka had been murdered, leaving behind a daughter and a wife who was brain damaged in a wheel chair and disoriented for reasons unknown. The case was still unsolved. Matou was part of a reasonably influential family headed by an old man named Zouken who had less than a shining reputation according to the rumourmongers in the city. A note from some of the Plumber investigators commented that Matou Kariya didn't have any signs of disease or failing health until the events leading up to the fire, in which he simply dropped dead in his family's home, in front of Zouken's adopted granddaughter of all people. Finally was Kotomine who was the son of the former priest of the church before he himself became one. The man himself seemed pretty average more than anything else and why he was possibly involved was a mystery in of itself. Still, he was the only one available to question about incidents who was alive and able to be contacted.

Ben rubbed his eyes to try and get the information sorted out in his head. Things were pretty vague about what the heck these seven people were doing, never mind the strangely-dressed people that were hanging out with them during the weird incidents. Several of the seven had relatives who were either in Fuyuki or some other country. Tohsaka had a daughter which was going to the local high school. Emiya had a biological daughter with Irisviel named Illyasviel in Germany along with a foster son named Shirou who lived in Fuyuki. Kariya had a nephew named Shinji and an adopted niece named Sakura, both of which went to the local high school like the other local teens.

'It's likely why they sent me,' Ben commented in his thoughts. Since most of the only leads were teenagers, then it would make sense to send a teenager to talk to them. Gwen might have been a good choice, but she wasn't as adaptive in fighting as Ben was and as many skills as Kevin was in many things, making friends really wasn't one of them. If Ben's fame did leak through to Japan, teenagers might actually be more willing to talk to him.

Looking out of the window, Ben saw that the sun was going down. The majority of the incidents both ten years ago and recently were occurring at night, meaning that whatever was responsible wanted to keep hidden for the time being. Of course, that meant he would have to do patrols at night to see if he could see anything suspicious. Fortunately the night sky would allow the likes of Jetray and Big Chill to avoid detection in the sky, even if Jetray was bright red.

Steeling himself, Ben travelled to the ground floor once again. He could have transformed on top of the building or just transformed in his room and leaped out of the window, but that wouldn't have been the best of ideas. On the off chance someone did see him flying around in the city, they would possibly try to follow him to wherever he called home. In a city where an unknown number of enemies may or may not be waiting for him, that would end up being a pretty bad thing. Exiting through the front doors, Ben stuck his hands in his pockets and began to travel down the streets, keeping an eye on his surroundings. All he needed was one private place to change and he could transform.

Spotting one such spot, Ben did a quick check to see if he was being followed before ducking into said alley. It was the basic alleyway so it had plenty of shade for him to use. Heading in deeper, Ben kept an eye on either end before he pulled his hands out of his pocket and began to reach for the Ultimatrix…

And then the hairs on the back of his neck began to rise.

It was a honed survival instinct that Ben had discovered was rather accurate during his many battles against the various forces of evil. No matter what form he was in or where he was, when that feeling hit him he knew that something bad was going to happen and it was going to happen fast! Obeying these instincts, Ben leaped forward, not even considering how he may look silly to any witnesses if he was wrong. He'd take a little humiliation over being killed in some painful way any day.

CLANG!

The sound of steel hitting asphalt was enough to let Ben know his instincts were right. Ducking into a roll, Ben turned to see who had attacked him. What he met was the image of a man dressed in blue with silver accents and shoulders. Despite being thin, his frame spoke of power and strength. His hair was blue and placed in a ponytail which went down his back. In his hands was a blood red spear which had its tip planted on the concrete where Ben had been standing a moment ago, the weapon actually breaking the stone surface. His eyes were actually red and a smirk was on his lips. What worried Ben more than the weird feeling he got from the spear though was the look in the man's eyes. It reminded him a little of the look Overlord wore, someone who got off on the battle for the sake of battle rather than belief in what they were fighting for.

"Not bad reflexes kid," the man smirked as he stood up and pulled his weapon out of the hole it made. "Not many can dodge me when they don't know I'm coming. Then again, I could tell you were something else when I sensed you out."

"Who the heck are you?" Ben asked with a frown, preparing to use the Ultimatrix in a flash. It didn't take a genius to know that he was going to need it.

"I could tell you my name, but you can just call me Lancer," the blue maniac grinned as he prepared his spear for another lunge.

Ben didn't waste any time waiting for the spear wielding lunatic to try and get him a second time. Quickly reaching for the Ultimatrix, he activated it and brought out the face of the machine before a hologram rose above the circular face of the machine. The hologram looked like a bulky suit of armour mixed with an old style stove. Ben didn't even need a second before he slammed the watch face down with a cry of, "Going hero!"

As Ben pressed the face of the Ultimatrix down, his entire world was bathed in green light. Within it, Ben's entire body lost substance, transforming into pure energy and becoming bright orange in the process. However, the change didn't stop there. The Ultimatrix disassembled with the face attaching itself to Ben's chest. The remaining pieces connected to the green hourglass symbol before beginning to transform into large pieces of cobalt coloured armour. Ben's torso was covered in a bulky round set with the Ultimatrix face centre on top of a raised circular section which connected to his back through a pair of tubes. His arms were covered in the same bulky armour with round shoulders and spiked manacles. His legs were covered similar pieces of armour with bulky feet. Finally his head was covered in a simple cylindrical helmet which had a grille not unlike a stove. The change was complete in less than a second, but Ben was already raring to go as the light died down revealing him as…

"NRG!" the new form of Ben Tennyson called out, his voice holding an accent similar to Russians, were they inside a hollow suit of armour.

"What the-?" Lancer gaped, honestly stunned into motionlessness at what he was looking at.

NRG didn't wait for Lancer to regain his full mental facilities. Rather, he simply charged at the blue-clad spearman, reading to pound him hard and hopefully take him out in one hit before letting the Plumbers figure out what was going on. The guy looked human enough, but NRG learned from experience that just because something looked normal didn't necessarily mean that it was. His grandparents were pretty good examples of that in themselves.

Lancer though, was obviously a veteran of combat and as such recovered quickly. Snapping back to attention, He leaped over the charging mass of steel and heat before twisting into the air and stabbing at NRG's back with his weapon. The tip of the spear glanced off of NRG's back like a rubber ball off of a wall. That wasn't entirely unexpected, but the fact that the armour didn't even show a scratch or even a dent from the impact from the weapon in question made Lancer's eyes widen. Just what was this guy's armour made of? His Noble Phantasm may have been at its strongest when he invoked its name, but even without its full power it was still a pretty damn powerful spear! It could cut through all sorts of things before being stopped. If it couldn't even dent this guy's armour…

Lancer began to grin at the thought. He was dealing with someone pretty damn tough. That was just great. He wanted a challenge before the War got started. It seemed like he got it.

Landing on the ground several feet back, Lancer grinned at NRG as the pseudo-Prypiatosian-B turned around to face him. "You seem to got some muscles in those arms and that armour's damn thick. Still, you're going to have to be quicker than that if you wanna beat me!"

"Bring it on," NRG replied before charging again.

NRG approached Lancer and swung at him wildly with his armoured fists. Lancer proved to be incredibly nimble as he swerved around the attacks, letting NRG's fists crash against the walls of the alley or the ground, making craters. Each miss just made Lancer smirk more as he saw the damage. Between each volley of punches, the blue-clad psycho would stab and swing at him, letting the blade of his weapon bounce off of his suit. Of course, the strikes would leave little, if any damage, but Lancer was aiming at joints and what he hoped to be soft points. He speed certainly allowed him such opportunities compared to how NRG was so slow. After attempting a swipe at his legs in such a fashion, Lancer leaped to the back of the alley to get himself some space.

"Man, this is getting to be entertaining!" the blue-haired man grinned. "You're trussed up tighter than any other knight I've ever seen. Hats off to whoever built that suit. If I didn't know any better I'd say you were a Servant or something." The comment made NRG's energy-composed eyebrow quirk, but he let Lancer continue. "Still, I think I've got your measure. All brawn and up close. You've got nothing in terms of range so if you don't mind, I'll take your mana now." Lancer reared back to throw his spear, confident that his natural speed and agility would allow him to pierce the one opening in NRG's armour and get the guy inside.

"Is that so?" NRG asked rhetorically. Immediately, the light behind his visor grille lit up before a beam of power burned through the air and seared towards Lancer. The spearman's eyes widened before he ducked out of the way, allowing the beam to continue on and collide against the side of a building at the end of the alley. Rather than the bricks blowing up like one would expect, they actually melted from the beam which NRG had fired. Seeing he missed, the armoured alien cut the flow of power in favour of eyeing Lancer again.

"Son of a-!" Lancer grunted as he eyed the end of his ponytail, watching it smoke with blackened edges. Turning to NRG, his eyes narrowed. He no longer saw this as just a simple tussle that he was eventually going to win. Now he was facing someone who was strong up close, but also had a damn good long-range attack too. He saw an actual fighter and an enemy that taking on with kids gloves amounted to suicide. "That's it! No more playing around!" Grabbing his weapon, he got in a kneeling position before he reared back his spear underneath his arm like a thrust, aiming the point at NRG again.

"Oh come on," NRG chuckled. "It didn't work the last fifty times so why should it-"

"GAE BOLG!"

NRG's reply was cut off as Lancer's weapon turned into red light before it seemed to just leap from his hand as he thrust the spear at him. The weapon streaked like lightning towards him with deadly intent. The armoured alien reacted quickly and fired a beam of his intense radioactive energy with the intent of melting the weapon out of the air. To his supreme shock though, the weapon actually darted out of the way from the beam and kept right on flying, even circling around the attack. NRG didn't even have any time to make a defence before the spear slammed into his chest directly over where his heart would be in his human form. The force of the blow actually took the psuedo-Prypiatosian-B off his feet before he flew out of the alley and crashed into a parked car, caving in the side. Thankfully, no one was inside of the car at the time. NRG could only groan slightly from the ringing in his non-existent ears. That had hurt! Looking down to the point of impact, his eyes widened to see the spear sticking out of his armour with a few good centimetres of the blade sticking into the steel.

"Holy crap," NRG gasped.

"What the hell? You weren't supposed to survive that! Gae Bolg always kills!" Lancer cried out, coming to the edge of the alley to gape at NRG's still living form. "Saber managing to survive I can understand…but you? Your armour must be a Noble Phantasm of some kind! Nothing else can stop Gae Bolg!"

"Cute. You named your spear," NRG grunted as he yanked said spear out of his armour. Tossing the red weapon aside and standing up, he eyed Lancer dangerously. "Now you're going to come with me an answer a few questions buddy. If you cooperate, I'll make sure you only get off with a light tan." He accentuated the threat by heating up his gauntlets, making them turn red from the temperature increase.

"Damn!" the Lancer growled. Still, he wasn't going to try to stop a fight as entertaining as this one. Another flurry of movement which NRG could barely catch and the Gae Bolg was back in the hands of its wielder, but Lancer didn't look as confident as he did before. His ace in the hole flunked and he wasn't sure if his usual tricks were going to be enough. There had to be some weakness that this walking toaster oven had hidden away. It just had to!

"Don't say I didn't warn you," NRG frowned as he began to advance. As he stepped closer towards Lancer though, the emblem on his chest began to blink red, making a deep beeping noise. Lancer blinked at the sight, but NRG on the other hand seemed to be finally beginning to lose his cool. "What? No! Not now!"

NRG was then suddenly enveloped in a flash of light, making Lancer shield his eyes for a moment. As the light died down, Lancer found that NRG was gone, and that Ben Tennyson was back in his normal form. At first Lancer wasn't sure if he was seeing things right, but then decided that he didn't care. The kid was out of the armour and that meant he was ripe for the kill once again. "Looks like you're out of juice there kid," the spear wielder grinned as he began to advance. Whatever that armour trick was, it didn't drain mana so Lancer was in for a decent snack. Hell, the kid was pretty much glowing with the stuff.

'Wait…glowing?'

Yes, the boy in green was glowing with a green aura which was visible to anyone who would have been looking. The boy didn't seem to notice it at first, his eyes being more trained on the spear Lancer wielded rather than himself. However, at Lancer's growing confusion, he began to notice for himself that something odd was going on.

"What the-?"

Those were the only words that Ben could get out as he noticed that he was glowing with bright green energy. Any further questions that he may have had about his current situation were drowned out when in a sudden blast of green power; a large circle etched itself into the ground, glowing as brightly as the aura surrounding Ben was. The circle itself was large, and had five smaller circles inside of it at the pentagonal points. Each of the circles had some kind of marking inside of them which depicted fire, water, earth, air, and lightning with the centre holding a rune which looked a little like a portal. It really was a piece of artwork but Ben was too busy shielding his eyes while Lancer was too busy freaking out.

"Oh no! OH HELL NO!" he snapped. "IT'S IMPOSSIBLE! THE SEVEN HAVE ALREADY BEEN SUMMONED!"

Ben would have asked what the heck Lancer was talking about when the centre of the artistic circle flashed brightly, blinding both witnesses and forcing them to cover their eyes so to save their eyesight. The illumination only flared for a moment before it died down. When the light did vanish, it took the seal with it but it had also left behind something, or rather someone.

This someone was in fact, female. She sported golden blonde hair which seemed to be slightly curly on top of her head while the rest was pulled back into a ruffled ponytail which ran down her back. Her eyes were a sapphire blue and against her pale skin, they seemed like actual gemstones. From head to toe, she was covered in ornate silver armour that despite it likely being made for a man, it had been tailored to fit her and it certainly made her figure noticeable. She was thin and trim like an athlete, but held the beauty and grace of a model. Her armour covered her torso, arms, and legs, all of it decorated with images of ivy along the chest and the sides of her arms and legs. What the armour did not cover was defended by chainmail which was just as polished as the rest of her armour. On her hip was a silver sword which had images of more ivy wrapped around the hilt and was resting in a white sheathe that was decorated with silver which made the image of a cross, if one included the hilt of the blade itself. On her opposite side and under her arm was a silver helmet which had a visor that would protect the eyes and had several long horizontal slits to see through while topped off with a long white feather trailing from the top like a ponytail. Despite the armour, the rather ornate but intimidating sword, and the eyes which revealed much experience in the ways of war, this woman looked like an angel.

An angel that was kneeling at Ben's feet, looking up at him expectantly.

"I ask of you, are you my Master?" the armoured woman asked in a pleasing, but somewhat hardened voice.

"Wha…what...huh?" These were the only words Ben could really get out. This was easily one of the strangest things that had happened to him and that was saying something. Usually the weird things ended up trying to attack him, not asking if they were his master of some kind. Well, not since he killed The Great One back when he was ten.

"I am Servant Avenger, heeding your summons," the woman spoke softly, an air of tranquility surrounding her causing even the battle-crazy Lancer to pause as events played out. "The Command Mantra you possess signifies you as a Master. My Master. As such, my sword and my skills are at your command."

Saying her piece, the woman stood up and turned to face Lancer. Eyeing him with her crystal orbs, she placed her helmet upon her head and suddenly she seemed no longer like an angel, but a warrior ready to do battle with any foe who stood in her way. She then drew her sword, revealing Latin words written across the flat of the blade. The noise of steel sliding against steel broke the tranquility and snapped Lancer out of his stupor. The blue-clad warrior smirked and took a stance as the silver knight stood across from him.

"I don't know what the hell's going on, but there's no way I'll turn down a fight like this!" he grinned as he prepared to strike.

The silver knight remained unresponsive to Lancer's words, concentrating solely on his actions as compared to her own. Things were still for only a moment between the pair before Lancer lost patience and immediately charged, aiming to pierce Avenger through her torso. Avenger was a flurry of movement, her armour glinting off of what light there was in the alley as she parried the blow before turning to slash at Lancer's body. Still, the blue warrior proved fast and experienced as he brought the end of his weapon up to block the blow from the silver sword. The impact brought sparks, but neither weapon was damaged. Needing space, Lancer immediately leaped up, travelling an inhuman height. However, Avenger wasn't far behind as she leaped up to continue the battle, the pair leaping off building sides and rooftops to clash with each other in the air.

Down below, Ben wasn't idle as he watched the battle going on, being very used to such sight. Instead, he was fiddling with the Ultimatrix, trying to get it to work again as he hoped that it would recharge soon, "Come on, come on!" he muttered, fiddling with the face. After a few moments of fiddling with the alien device, the face turned from red to green, indicating that the machine was ready to use once again. "All right!" Activating the face, he brought up the image of what appeared to be a moth man with large wings. "Let's see if you're hot enough for Big Chill!" Ben commented as he slapped down on the face.

Another green flash erupted and Ben quickly began to transform. His entire body bulked up with an inhuman amount of muscles, giving him several feet in height to accommodate it all. Further changes continued as a new pair of arms grew from his torso, just as muscular as his first pair had become. His skin turned deep red while his skull reconfigured to allow a second pair of eyes and his hair turned black before being pulled into a ponytail at the back. The Ultimatrix reconfigured the molecular composition of his clothes, becoming a gold bandolier across his chest with the Ultimatrix with matching gold bands on all four of his wrists and both ankles. Lastly was his pants turning into a pair of briefs like Superman would wear, only black with a gold belt leaving his muscled legs free motion in case of anything happening. Slamming his fists together, the new alien cried out his name.

"Fourarms!" the pseudo-Tetramand bellowed…and then blinked as he got a look at himself. "Man, of all the times to start being smart with me," sighing, he looked up to see Avenger and Lancer moving their battle to one of the rooftops rather than simply clashing in the air as they leaped at one another. "Oh well, might as well make the most of it."

Eyeing the rooftop where Avenger and Lancer were fighting, Fourarms charged down the street before taking a giant leap. His legs easily propelled him through the air before he caught the window ledge on the side of the building in which Lancer and Archer were fighting on top of. Despite his weight and gravity pushing down on him, Fourarms propelled himself up by two arms, gripping another window ledge and pulling himself up even further. Another leap got him to the edge of the rooftop before he pulled himself over, spotting the two warriors in a heartbeat. Lancer had his back to him with his weapon pinned against Avenger's both warriors attempting to overpower one another for dominance.

Fourarms didn't need more of an invitation than that. Getting to his feet, he charged at Lancer's exposed back before leaping the rest of the distance, aiming to let gravity, his muscles, and his weight take down Lancer in one fell swoop. "Hey blue boy! Forget about me?"

Lancer turned his head only a fraction so he could see who was yelling at him while keeping Avenger in his sights at the same time. Seeing Fourarms coming down at him made the spear wielder quickly forget about his silver-clad opponent and instead leaped to the sidelines at a speed that would have Olympic athletes struggling to match. Fourarms came down hard, shattering the surface of the roof and making shards of concrete fly in many directions. Avenger had the natural reflexes to likewise back away when she saw Fourarms approaching so she managed to avoid being accidentally struck.

"Dammit!" Lancer cursed as he got to his feet. Now he was squaring off against Avenger and the four-armed freak. Even freakier than though was the fact that Lancer could detect the mana signature of that kid with the green jacket he tried to off, kick-starting this whole fight. The two on one odds didn't really bother him, since that just meant more fun in his mind. What did bother him was the unknown element brought in by the supposed Servant Avenger and the shape-shifting kid who was her Master. The brat had already been some kind of heavily armoured thing and now he was muscle bound with four arms. Gods above only knew what else he might be able to turn into.

Lancer wasn't the only one surprised by Fourarm's appearance. Avenger was very much stunned at the sight of the Tetramand standing next to her. Were it not for the fact that the mana which was being supplied to her came from the strange beast, she would have thought some kind of mutated familiar or infernal minion was assisting her in battle. As it were, she recognized the creature as her Master. It was all she could do to not stop and gape in the middle of the battle when she discovered that little fact. Of all of the things she expected from a Master upon her summoning, THIS was surely not one of them.

"Not quite what I was expecting tonight, but I sure as hell ain't complaining," Lancer grinned as he twirled his spear and took a battle stance. Fourarms and Avenger both got ready for another assault, knowing just how good Lancer was with his weapon of choice not to mention having the speed to match said skill. Avenger was prepared for battle while Fourarms just wished that he was in a faster form so he could keep up with the lunatic. As it was, he was just going to have to deal with what he had. Gripping his fists, he prepared to go for another charge when…

"Eh?" Lancer suddenly dropped his stance as if someone was talking to him. "Hey! Wait a second! I'm in the middle of something here!"

Fourarms quirked his left eyes as he watched what essentially seemed like Lancer getting into an argument with himself, "Uh, who's he talking to?"

"Likely his Master," Avenger commented softly, her voice sounding deeper behind her helmet.

"So someone's pulling his strings then," Fourarms growled. "I hate when things get complicated like that."

"Of course I know my orders!" Lancer snapped at his unseen Master. Snarling, he turned to gaze in resignation at both Avenger and Fourarms. "It seems that things were just getting interesting. A shame my Master is a coward. Feel free to follow me though. It'll give me an excuse to finish this!" Eyeing the pair a final time, Lancer took off towards the edge of the rooftop before leaping straight off without hesitation. Avenger and Fourarms quickly dashed to the edge to see what became of the blue-clad killer, but quickly found him leaping and bounding away. He was already a fair distance away, likely using his full speed.

"Don't think even Jetray could catch up to him at this point," Fourarms frowned. "Crud."

Sighing, Fourarms reached to icon on his chest before a green flash was released, returning Ben Tennyson to his natural form. The sudden shape-shifting was almost as natural as breathing for Ben, having wielded both the Omnitrix and now the Ultimatrix for some time. His closest friends and family were likewise used to it, although his parents tried not to let it bother them too much knowing that their son had helped save the entire universe from destruction. As calm and accustomed as the people who knew Ben personally had become concerning his transformations, the people who only knew him by reputation or those who had just met him the transformations were…shocking.

"M-Master," Avenger spoke, the steel draining from her voice, but not entirely. "If it is not offensive of me to ask, but…what are you?"

Ben could tell that Avenger was clearly uncomfortable despite how tough she clearly was and quickly tried to reassure her, "Hey, I'm just a regular human. It's not like I'm a monster or anything. I just have something which can make me transform like that," Ben was hesitant to explain the Ultimatrix. Pretty much everyone knew he used it to transform into his alien forms, but no one knew the story of where it came from or who had built it. That was a closely guarded secret. "What about you though? Just how the heck did you get here? Why do you keep calling me Master?"

"It was you whom activated the summoning spell, was it not?" asked Avenger. Ben would have wagered that there was curiosity in her voice, but only in a rhetoric sense. Instead of waiting for any kind of reply, she pointed at Ben's right hand. "The Command Spells are engraved on your hand. They signify you as a Master. My Master to be specific."

"My hand?" Ben blinked, looking down at his right hand. To his shock, red lines were marked on the back of his hand, glowing in the night. As a whole, the markings looked like a shield which was split into three parts. A top section, a middle, and a bottom were all accounted for. By themselves, the markings just looked like a mix between runic and creative styles of tattoo artistry. "Woah…" Ben could feel that the markings were more than just ink doodles, but he still hoped just the same that he could get rid of them before he had to go back to Bellwood or else Gwen was really going to let him have it, never mind what his mom would do.

"Okay…but do they do anything else?" Ben knew, from experience, that things which seemed to appear out of nowhere had a tendency to do more than just sit where they've been put and look ominous.

"They are absolute orders," Avenger replied, her voice appearing a little reluctant on the subject, but it was hard to tell what she was feeling since she was still wearing her helmet. "Should you activate one while giving me an order, I will not be able to disobey it. However, using one causes it to vanish, so only three such orders are available."

Ben blinked at the notion of such casual slavery, but also began feeling like he had been dropped in the middle of the ocean and told to swim. It was a feeling he got when the Highbreed started making their appearance on Earth, likewise when his identity got blown and that mess with Aggregor got started. Sighing, she scratched his temple, "Okay, I think some more detailed explanations are going to be needed here. From the beginning. You seem to know what's going on, but I definitely don't."

"Very well Master," Avenger nodded, but her gaze seemed more focused on their surroundings. Well, it seemed to be since that helmet of hers made it hard to tell if she was looking at him or not. "Is there anyplace else we can speak privately? What I have to say is not meant for just anyone to hear and must be kept secret from the people at large."

"Well…," Ben rubbed the back of his neck, glancing at their surroundings. "Sure. But…how are we going to get back without anyone noticing you? Armour and swords don't exactly blend in these days."

"Easily done Master," Avenger nodded. She was still for only a moment but then quite suddenly she seemed to fade into a transparent version of herself.

"What the-?" Ben gaped.

"Please do not panic," Avenger spoke softly. "I have merely restricted the mana flow from you to me so that I take on an astral form. Only you can see me, no one else. I also have the ability to fly in this form so I may follow you anywhere or get to you very quickly."

"Uh…okay…" Ben blinked. Mana? He had mana? He remembered Gwen telling him that mana was the energy which she manipulated in order to use her abilities. Since she took more after their grandmother than he did, she had a pretty big reserve of the stuff. Ben on the other hand didn't think he had any, but maybe since he was related his grandmother, a being made of pure mana, he may have a touch of it after all. Well, enough to bring out Avenger anyway.

"Shall we go then Master?" asked Avenger.

"R-right," Ben nodded. Activating the Ultimatrix once again, he cycled through the numerous aliens which were available, many of them bringing curious looks from Avenger on each one. Finally, Ben settled on one of his most-used forms before slamming the face of the device down. The green flash typical with the transformation followed before Ben's frame grew taller, but much skinnier. His bones hollowed out for flight while thin bands of skin stretched out to connect his increasingly longer arms, similar to bat wings, but styled more like a stingray's. His head turned square-like with green eyes and a pair of red horns atop his bow as a long tail shifted out from behind. Black fringes not unlike gills etched themselves into his sides as the Ultimatrix symbol appeared in the centre of his chest. "Jetray!"

Avenger couldn't help but blink at the red creature which had been her master only a moment before, "Curious."

"Follow me," Jetray motioned before he took off into the air, gliding on the air currents. Avenger quickly followed, flying through the air as if she were nothing more than a ghost. The pair quickly cut through the air, but Jetray purposefully kept slow so Avenger could keep up. Soon enough, the pair landed atop the hotel that Ben was staying in. The door was sadly locked, but one nueroshock blast from Jetray's eyes destroyed the lock and rendered the door open. With that minor task taken care of, Jetray returned to the form of Ben Tennyson.

"This way," the green-clad boy gestured to the ghostly Avenger.

Ben and Avenger quietly travelled through the stairs before exiting into the hallways where Ben's room was located. The teenager was slightly concerned about someone spotting Avenger even if she claimed that no one would be able to see her. Things were rarely that good for Ben when he found himself in the middle of a new and strange situation. Knowing his luck, he'd bump into something or someone that was capable of seeing Avenger in her spiritual form and flip out.

With no incident, Avenger and Ben reached the young man's room. Avenger quickly entered and Ben shut the door behind her, taking care to lock it in case someone from room service decided to come inside, thinking he was gone or something. As the lock slid into place, Avenger returned to her solid form, removing her helmet and shaking her hair so to get it fanned out once again.

"Thank-you Master," she spoke, relief in her voice. "Usually it is the Master which employs that technique by cutting off their mana supply. If I do it, I begin to feel pressure within my body."

"Sure," Ben nodded as he headed towards the living room, "So, can I get an explanation as to just what the heck is going on?"

"Yes Master," Avenger nodded, slowly following. Ben sat down in a chair as Avenger took a spot in front of him. "As I stated before, I am Servant Avenger. I am to be your sword and shield for the duration of the Holy Grail War."

"Wait…Holy Grail?" Ben blinked. "You mean THE Holy Grail? The cup of Christ? The most sought after religious artefact of all time?"

"Sadly no," Avenger shook her head. "The term Holy Grail applies to a powerful artefact which appears in a cycle of fifty years or so. When it appears, the Grail War begins. It is a competition between seven Masters and their Servants. Whoever is the last one standing shall be the one to claim the Grail and receive a wish for anything they desire."

Ben blinked at the rather brief and succinct description, "Woah. So…when you say anything, does that mean…?"

"Anything," Avenger stated. "Anything that can be conceived by your mind can be granted to you for winning. You Master, were selected to take part in this competition."

"Wow," Ben blinked. The sheer importance of what was happening wasn't lost on him. Were he still ten, he might have been stoked to take part for a chance to win a wish at anything he wanted. Now that he was older and had a bit more world experience, Ben could guess that with a prize that powerful on the line, no one else who was competing would be pulling their punches. "Okay…so that guy Lancer. Was he a Servant too?"

"Yes," Avenger nodded. "Lancer is not his true name, while Avenger is not mine, but the name of our classes which we are designated. It is safer that we be referred as such."

"Right," Ben sighed, not quite understanding. "So why did Lancer attack me? Was he able to tell that I was going to be a Master or something?"

"Again, no," Avenger denied. "We Servants are dependant on mana to keep ourselves in this world. Should we run out, we will fade away and be officially eliminated from the War. If our Masters cannot supply it, we will be forced to drain it from other people by draining their souls."

"What?" Ben cried. That Lancer guy wanted to steal his soul? "Wait, what about you? Do you need to do that too?"

"Never!" Avenger snapped, clearly disgusted with the thought of doing such a thing. "I find the act disgusting and downright evil! I would rather vanish than take part in such a thing! Fortunately, the mana in which I receive from you is sufficient for my needs."

"That's good," Ben sighed in relief, letting his head hang. "Grandma said I didn't have the 'spark', but I guess there's something to be said for being related to an Anodite."

"What is an 'Anodite'?" Avenger asked, having overheard Ben's mutterings. "Is that another word for a Magus?"

'Crap!' Ben cursed mentally. While Avenger was no doubt in the loop about something big in which the general public couldn't know about, Ben didn't want to reveal more about aliens and the Ultimatrix than he had to. Thinking quickly, he decided to go along with Avenger's assumption, finding it to be a better cover than anything he could think up of on the fly. "Uh…something like that, yes. Grandma is able to use mana pretty much without limit and my cousin's pretty good with it too."

"Then if you come from a family of mages, should you not already know of this?" asked Avenger curiously.

"I don't think any of us have heard of something like this," Ben replied confidently.

"I see," Avenger nodded. "In that case, you should know that there is a moderator for the War. He can be found in the local Catholic Church. You will have to register as a combatant there if you wish to be recognized by the Grail. He can also answer any questions you may have about how the war works."

"Okay then," Ben nodded. At least he would be able to get some answers then. Still, Ben was feeling apprehensive about taking part in the Grail War. Granted, the prize was worth fighting for to his materialistic side, but there was more to consider than just that. There were also the other combatants to consider. Just how far were they willing to go to win this war? What kind of wish did they have? If they were anything like Lancer, then it was important that they didn't get their hands on the Grail. If someone who so callously sacrificed the lives of others to keep himself in the fight won, then it could mean something as bad as Ultimate Aggregor or Vilgax with the Omnitrix. That alone made Ben positive that by this point he had to compete.

Turning to view a nearby clock, Ben found that he while he was out; the time had passed for the city's official curfew to begin. One of the many security measures that the city officials had enacted in order to try and protect people from harm. Of course, if there were any more like Lancer running around then it wasn't going to matter if anyone was out in the streets or not. They were simply fuel for the creep and likely to be nothing more. Ben knew that Lancer, and thus his Master had to be stopped.

"It's late now and I doubt the local priest is going to be awake or at the church right now," Ben commented. "We'll have to see him in the morning. I don't want to agree to joining in just to spend time in lockup for breaking the curfew around here."

"Very well Master," Avenger nodded.

Miyama-Kotomine Church

Kotomine Kirei sat in his chair, looking over the notes for his next sermon. However, his mind was not on his work but was merely a distraction from his current predicament. He had seen through Lancer's eyes at the American boy who transformed into two different monsters and then summoned a Servant even though the seven have already been called forth. He knew very well what the Servant was. Avenger had only been seen once in the history of the Grail War and that was during the third. Since then, that Avenger's soul had been trapped in the Grail, tainting it with the dark wishes his people had when the poor soul was sacrificed for their beliefs. That made it a truly worthy prize to the priest. It was something he wanted to be born into the world so he could see just what would happen. He had his chance during the last war, but that meddler Emiya Kiritsugu destroyed it, preventing it's appearance for what was though to be fifty years but instead only for ten. When the new war started, Kiriei thought he lucked out, but now Avenger had appeared again.

Kiriei found himself in a quandary now. Avenger was unpredictable since there had only ever been one before and Kirei hadn't been there. He didn't know why the previous Avenger was trapped in the grail nor why he had been summoned. There was no record as to how he fought nor how strong he had been. Not even the Grail granted Kirei that knowledge. No, a true wild card had appeared along with a potentially powerful master. A priest Kriei may have been, but he wasn't a shut-in like the stereotype made priests out to be. No, Kirei knew about Ben Tennyson and the fame he collected over in America. Japan at large may not know of him, but the Catholic Church definitely kept an eye on him and his strange power to transform into creatures not seen before by anyone. Some in the Catholic Church opted to try and steal the device he used or recruit him in their quarrels with the mages, but that was vetoed since attempting to take it would turn him against their organization and simply spouting their rhetoric on mages would do the same. The boy was too liberal to be convinced by their archaic reasoning.

"You seem quite concerned," a suave and calm voice spoke up.

Kirei looked to the door to his office and spotted a blonde-haired man with red eyes standing in the doorframe. The man exuded a charisma which instantly made him seem trustworthy and capable of befriending someone. Even dressed casually he seemed to hold a grace fit for a king that couldn't be extinguished even if you covered him in cow manure.

Ironic since the man before him was hailed as the King of Heroes.

"The War has been given a wild card like none before and he's been given a Servant that only appeared once before and is responsible for the current state of the Grail," Kiriei answered patiently. He knew better than to be his usually innocently aggravating self to this man. He'd be reduced to a red paste in but a moment.

"Hmm, and here I thought the only interesting points of this War would be the demi-god and Saber," the man smiled, although the eagerness for battle was quite clear in his eyes. Hiding emotions had no real purpose to him. "Just who is this wild card?"

"If what I saw through Lancer's eyes was right, his name is Ben Tennyson," Kirei answered. "He's quite famous over in America. Quite the hero."

"A hero?" the man asked with a raised eyebrow. "I will be more than willing to test that claim."

"I daresay you'll get your chance," Kirei replied. "He should be coming in to the Church soon if Avenger is following the rules. Who knows? Maybe you'll see something you'll like."

"Perhaps," the golden-haired man shrugged, although his actions seem to speak of not having much hope of that. Shrugging, he turned around and began walking away. "I feel like topping off my mana. I'll be back."

"Of course," Kirei nodded, looking back to his papers. His thoughts once again tried to distract him from the possible implications of an 8th Servant and her Master as he tried to complete his next sermon. The boy and his knight could be dealt with in time. They were merely a complication, nothing more. Once he had enough information, they could be dealt with. If they should truly make themselves into a threat or worse, there was always Gilgamesh ready to deal with them.

To Be Continued…

A/N: Hey everyone. This whole story idea just popped into my head one day and it just wouldn't leave so I had to get into in writing or else it was going to drive me insane. Chapter 1 is a little short, I admit it but this started out as just a one shot idea for the Idea Farm. Soon after, it took on a life of its own and became a full-blown story. So now this chapter is just to set the stage, introduce Avenger, and get Ben started onto his path through the Holy Grail War.

This story won't be following Fate, Unlimited Blade Works, or Heaven's Feel scenarios although there will be elements from each of them. This isn't a simple 'put a new character into another's place and follow the same plot' kind of fic. Ben's been added to the mix rather than replacing a puzzle piece so his actions and appearances are going to bring about consequences and changes. For those of you wondering how an eighth Servant got involved in this, that will be explained later.