This is a new experiment for me. I'm used to writing crossovers, but this is the first time I'll write an original story for a crossover. Until now, I've mostly been following anime stories or book stories. So I hope I do this idea justice.

Chapter 1: The Watch of Heroes

Ben Tennyson's latest mission wasn't too difficult. They had learned of a mage that had been kidnapping random, almost-won't-be-missed people. They didn't know what for, but a cynical part of Ben said that the victims are beyond any help. So they called his cousin Gwen in to help. She was a prodigy with magic, and might be able to undo whatever this creep was doing. She and her boyfriend, Kevin, had agreed to head on back to Bellwood from College to help out.

"Approaching the suspect's home." His partner, Rook Blonko, told everyone. "Get ready for forced entry."

"Yeah, yeah." Kevin muttered. "We've done things like this a dozen times, Rook. We can handle a magic dude." Kevin was tall, with long dark hair and muscles everywhere. He and Ben had used to be enemies, but now they were best friends.

"Don't get overconfident." Gwen told him off. As expected of a redhead, she was very fiery and tough. "We don't even know what this guy can do. And from the spells I'm reading, anything involving blood can't be good."

"That's what you're here for." Ben replied. "Me, Kevin and Rook keep this guy and his monster busy, while you shut down his spell. We beat his monster, we lock him up in the Plumber prisons, and then we all go out for smoothies. Simple."

"Whenever you're around, Ben, things are never simple." Still, Gwen couldn't fault him for his optimism. They'll figure out something to stop this creep.

By now, they had pulled up over the Mage's house. It was a simple, rundown looking place, all the easier to hide. Rook used his Omnitool to slice a hole in the roof, while Ben used Bloxx to lower it carefully. They didn't want the guy knowing they were there until Ben's fist was in his cheek. As they went down into the basement, they could hear someone chanting. Ben used Ghostfreak to spy on what the creep was doing.

It was a magic circle of some kind, made with what Ben hoped was red paint. It had strange symbols round the edges and was giving off sparks from the magic. In the center was what looked like a battered, horned helm. As Ben moved slightly to see the rest of the room, he finally spotted the missing people. Just as he feared, they were all dead, drained of blood with their throats slit. It took all the self-control he had to not just start pounding the bastard right now. Instead, he moved back to the others, and gave them the signal. As they charged in, Ben moved round to the other side, and gave the mage a solid blow to the face.

He cried out as he went flying, before smashing into Kevin's stone fist. But before Rook could land a follow-up blow, the mage fired a blast of fire everywhere, setting the whole place on fire. Ben quickly changed into Heatblast, and drew in all the flames. They didn't want to go up with the building. While everyone was distracted, the mage grabbed a briefcase, chanted a spell, and threw it onto the ground. It opened up, revealing a dark, shadowy monster. Kevin yelled as it scoured some lines in his skin with its claws, while Rook was barely able to defend himself by shoving the Omnitool into its mouth. Ben tried to help, but a tail came out of nowhere and smacked him into the wall near Gwen. He groaned. That blow had really hurt. They had to shut down that spell now.

"How we doing Gwen?" He asked as Kevin and Rook had a game of Keep-away.

"Hold on." Gwen replied angrily. "This spell is complicated. I've never even come across anything this complex."

"Well hurry. I don't think Fido's interested in playing fetch." At this, the tail swung at him again, causing him to roll away. But the only direction available was towards the circle.

As his Omnitrix touched the circle, something weird happened.

It started beeping loudly and forced Ben to change back. As he turned to normal, the Omnitrix started glowing bright green, before changing into a variety of colours.

"Aw man." Ben groaned. "Now? Really? You couldn't start having a meltdown five minutes from now?" He dodged as the mage fired another fire blast at him, nearly getting severed by the monster's jaw. As he backpedalled, Gwen saved him by throwing the monster into a wall. "I thought you had to disable the spell."

"Somehow you touching it shut the whole thing down." Gwen said as she pulled him up. The Omnitrix started glowing with a flash of light, blight everybody. When they could all see again, they noticed that it had a new look.

It now appeared to be made of gold and precious gems, with the face plate having an emerald inset into it. It also appeared to be a glove again, like the Ultimatrix. Ben quickly activated it and looked for a good form, but all her could see were strange symbols. "Oh man. You're still malfunctioning?"

"Tennyson!" Kevin shouted as he wrestled with the monster. "We need something. Now!" Ben just chose a random symbol, showing a horse and a horn, and pushed it down. He felt different as he changed. Normally, he felt like his muscles were stretching or contracting as he changed form. But now it was more like he was getting pulled apart and put back together. He stumbled as he got back to his feet, noticing he was still a two-legged form. He had a quick glance at a broken mirror, and nearly stopped to stare.

He was a girl with rose-coloured hair and a short armoured skirt. He had long black stockings attached to something under the skirt, and a white cape draped over his shoulders. Luckily, he also had a sword by his side. He pulled it free and started slashing at the monster. For some reason, he instinctly knew how to use it, a far cry from when he had Ascalon. The monster squealed as he sliced away at its limbs until Kevin finally threw what was left at the wall. While this was happening, Gwen was busy having a magic duel with the mage. Sure he clearly had more power. But Gwen had a wide variety of spells to hit him with. He was knocked away and tied up, but the wall shattered and revealed several more suitcases. They looked on in horror as they opened up and started spawning more monsters. The mage untied himself and ran up the stairs, but his monsters chased him up with Ben and his gang right behind them. They heard people screaming as they crashed through the door, showing the monsters chasing people.

I need to get everyone's attention. Ben thought to himself until his hand brushed against a horn. It was an old-fashioned one, meant to look exactly like a bull horn. Perfect. He pulled it from its hook and was about to blow on it. But something kept coming to mind and distracting him. "Ok, then." He said in a strange boyish voice. "What the heck is La Black Luna?" He yelped as the horn started growing, circling around him as pipes started sprouting like mushrooms. It only took a few seconds before he was holding a massive trombone thing instead. He shrugged, and blew on it.

The effects were immediate. Everyone, including the monsters and his friends, started screaming even louder and ran away from him. The monsters whimpered and raced back into the house, which they only just realised was burning down. The horn shrunk again until it was back to normal, and Ben was left standing bemused. Weird. Thy found the mage easily enough though. He hadn't made it far before his monsters ate him up. Everyone was coming back round, looking at them in awe.

"Uh…There we go." Ben said. "We totally took care of that mage. I'm not too sure how I did that, but it was awesome. And weird."

"That was awesome." Some guy said as he came closer while everyone was checking each other over. "You know, I've always wanted a girl like you."

"Huh? Oh, I'm not really…" Ben blushed as he hit the Omnitrix, then looked in confusion as he stayed the same. No. Not another malfunction. As he looked at it in confusion, he felt the guy place his hands on him.

"So how about it? I'm pretty sure that heroines get a 'reward'." He forced a kiss on Ben, while putting one hand under his skirt. Ben was about to deck the creep when he felt something unusual yet familiar being touched. The creep looked in horror. "Holy shit! You're not a lady, you're a dude!"

"I am?" Ben asked dumbly, turning around and pulling at his skirt to look. Yep, just like he said, Ben was still a guy. A guy that looked like a crossdresser. He turned back around just in time to see a girl slap the guy in anger. Guess he already had a girlfriend. Well, he'd better head to Plumber HQ and figure this thing out. He walked back over to the others, who were looking at a weird symbol on Gwen's hand. It looked like a magic circle, divided into three parts.

"Hey guys." Ben greeted them. "So apparently, I'm actually still a guy." They looked at him in confusion. "Don't ask how I found out. Also, I can't change back to normal for some weird reason."

"Typical." Kevin groaned. "C'mon. Blukic and Driba will need to have another look at you. And Gwen needs to learn what this symbol means."

"Right"

Ben knew the other told him not to, but he still fiddled with the Omnitrix on the trip home. He kept tapping and slamming at it, but it didn't even react. Don't tell him he was stuck like this forever? As he slammed on it one last time, he hand twisted slightly, and turned the dial. He changed in a flash of light, once again feeling as if he was being pulled apart and put back together again. He quickly looked in a reflective panel to see he had changed. A bit. He still looked like a girl, but now he had blond hair and a red dress. In fact, as he looked lower, he realised he was a real girl this time.

"Oh by the fate of fate." He said in a girly voice. "To have gone from a mere boy dressed as a girl to one that clearly is of the fairer gender is not quite the answer I desired. Although it is a much better look for one such as myself. Now, if only I could stop speaking as though I was Brainstorm on the set of a mighty play." Kevin started laughing as he turned to face them. Ben rolled his eyes. He knew being a real girl was embarrassing, but Kevin didn't have to laugh so much. "Does my yonder predicament find you most joyous Kevin? It is not meant to be a comedy of your interest."

"I think you might want to look a bit lower Ben." Gwen said as she started giggling. Ben looked at her with a level gaze before finding a full-length panel. He gasped as he saw his… dress.

"What manner of bewitchery is this? To have fallen so low, and yet feel not even a hint of shame. Why in all the pits of the Underworld is the front of my dress revealing mine undergarments?"

"That's why I told you not to touch it." Gwen replied as she turned back to the information panel. Ben sulked until a large crimson spiked sword suddenly appeared in his hands. He gave it a couple of test swings, noticing how light it was despite its size.

"Why, just look at thy noble weapon. Such grace, such power, and such elegance. This is one bitchin sword."

"Ben!"

Grandpa Max sighed as he saw his grandson, stuck in a strange and revealing form. He never once thought he would have to worry about him wearing something too risqué. He always thought that might be Gwen.

"So explain this to me again." He said. "You guys went in to stop the mage, but Ben came in contact with the magic circle and the Omnitrix malfunctioned. Then it started working again, only now Ben can only turn into people."

"Girls or dudes that look like girls." Kevin said helpfully.

"And now he can't change back. He can only change into other forms. And meanwhile, Gwen has got a magic symbol on the back of her hand that we don't know what it does." He sighed and massaged his head as all this piled up. You'd think that by now he'd be used to this kind of stuff. I mean, just last week a collector from another dimension showed up to collect Earth. But every now and them, Ben just threw him another curveball. "Let's just see how Blukic and Driba are doing." They exited his office and walked down the halls, passing agents going to check out the house in case there were more of those monsters. They finally entered the main lab to find Ben squirming away in his seat.

"Will you just hold still?" Driba said as he looked at the computer screen streaming in all this weird data. "This is hard enough without you making it more difficult."

"Believe me, oh tiny scholar of technology, I would most certainly stop squirming to be out of this form as fast as Mercury." Ben said in his theatre-like tone, wincing and twisting all the while. "But I would not be reduced to this if Blukic would kindly stop rubbing against my breasts." Gwen blushed as she realised Ben's moans weren't exactly because of pain. He moaned again as Blukic pushed aside a mountain of flesh.

"Well, if you hadn't gotten the Omnitrix stuck between your boobs, I wouldn't be having to work under such hazardous areas." Blukic said as he tapped the Omnitrix again, the panel open. From what they could see, some weird energy was moving around inside the Omnitrix. Blukic fiddled with something, before closing the panel and turning it. As the light faded, Blukic got crushed as Ben's breasts grew even bigger, now robed in a purple-and-black dress. His eyes were covered by a cloth, and his face was hidden behind long purple hair.

"Ok then." Driba said as he went to pull Blukic out. Ben blindly groped himself until he finally found him, and pushed aside his breasts long enough for the small alien to escape. "From what we can gather, the Omnitrix is not picking up its internal servers anymore. Instead, it's tapping into some kind of 'magic server' with different forms. But we're not too sure what this server might be."

"I think I might have an idea." Gwen said as she looked at a spellbook they had rescued. "But I need a small animal to test a theory with." Rook just shrugged and went off to find one. Ben got up and walked around a bit, stretching his legs. Strangely, he didn't walk into anything, moving similar to Wildmutt. It took several minutes, But Rook came back with a small bunny. "Great. Place it in the centre of the lab. Everyone else, stand behind Ben." They all got moving, Rook placing th cage with the bunny down on the ground before standing right behind Ben. "Now Ben. Last time, when you used the horn, you said something to activate it. Could you figure out what to say to activate your eyes?"

"I'll try." Ben said in a seductive voice. He stood there, looking at the bunny before finally speaking. "Breaker Gorgon." The band around his eyes fell to the ground, and the effects were immediate. The bunny turned completely into stone. Ben stooped down to grab the band, and wrapped it around his eyes. Gwen could feel a slight change in mana when it wrapped around his face. They all stepped closer, looking at the petrified rabbit. Ben changed his form back into the first boy, looking at the rabbit in surprise.

"Ben." Gwen whispered. "I figured it out. I don't know how you're doing it, or why such a thing exists. But you turned into the Gorgon Medusa."

"I think you're turning into historical people."

Far away in Japan, in the city of Fuyuki, The Grail reformed. It was ready to begin the Holy Grail War. It was ready to mark Magi to summon heroes.

And it stopped, realising that a Heroic Spirit was already active. In America. And this hero was different. It was a direct line to the Throne of Heroes, even more direct than the Grail. Angra Mainyu smiled as it realised this. True, it would be difficult to complete the ritual outside of Fuyuki. But he could sense the opening to a powerful realm. One previously inhabited by a god-like monster. That will be a good staging ground. So instead, it sent itself to this realm, feeling the power coursing through it. And then it chose any masters waiting in this land.

While some will try to stop him, Angra Mainyu wasn't worried. There were enough people who'd do anything for a chance to wish for anything.

All he had to do, was wait.

Beth Ravensquire grimaced as she tried to perfect her spell again. It wasn't fair. It wasn't fair. Her spell worked perfectly before. Sure, being able to teleport things into people wasn't what she really wanted to be famous for, but it was a step in the right direction. But instead of teleporting a piece of cheese into a rat, she somehow managed to teleport its stomach 3 feet outside its body. And the cheese ended up halfway through the skull. All the other students laughed at her when she failed, and her thesis was ripped up. But she was going to show them. You don't have to come from great places to be famous. She was going to be the best heroine ever. Like Ben Tennyson.

"Just you wait Ben." She said to the poster on her wall. "We'll show them that we're awesome. And then maybe I can become your sidekick. And if things work out well, your friend. And if that goes well, then I might even be your girlfriend." She sighed as she imagined them together, a battle couple that fight evil at day, and make love at night. She suddenly hissed in pain as her hand burned, before accidently knocking the cheese she had been experimenting with under the bed. "No. No, no, no. You can't run on me. I was so close." But despite her scrabbling, she couldn't reach the cheese. Great. Now she was going to get a rat under her bed. And she still didn't know what hurt her in the first place. She looked down at her hand to find a strange symbol. It looked like Ben's logo, with spiky lines all over. Something about that seemed familiar. She could've sworn she heard it from a class back at the Clock Tower before she moved out to this glorified school shed they called 'The Shed'. Classy.

"Many Magi in the past found themselves with markings on their hands." Professor El-Melloi II told them. "These markings showed that the Magus was chosen to fight it the Holy Grail War. But we have recently discovered that the Holy Grail was infected by all the world's evils, and has been corrupted. We have dismantled it, and so if any students find themselves with these markings, they are to alert their tutors at once so we can destroy it again."

Beth was nearly about to tell her teacher when something else came to mind. Fellow students said that the Grail could grant any wish. That was why they wanted to be alerted. So they could get the wish for themselves. She didn't really care about that kind of paranoid wish-wash. But she realised that any wish could include perfecting her technique. Hell, it could even mean partnering with Ben Tennyson.

Let's not get ahead of ourselves, Bri. She warned herself. You can't be a hero if you force him to choose you. But if you were to have really cool powers, then you could still get his attention. She squealed in excitement as she realised all the doors now open to her.

She just had to figure out who to summon and where to go.

Damian Vander grunted in pain as the thugs kicked him again. They laughed as he puked out all the beer he had ingested just an hour ago. If they knew that he was a Magus, they would be pleading for their lives. Well, actually they'd probably just laugh some more. To think he has gone from that to being a drunken homeless man. But he had nothing to go back to. His family was dead, and every coin he had then was put towards a manor that fell apart from a simple earthquake. And now every last penny he got scrounging went to beer. There had to be some sing for him. Was he going to be something great again, the envy of all others? Or was he doomed to die in the gutter here, a nothing and a nobody?

As he looked at his hands with blurry eyes, he noticed the symbol on the back of left hand. It was a sword, the old symbol of his family, surrounded by two halves of a shield. Suddenly, he remembered what they meant. A mark of a Master. The Holy Grail War. A chance to wish for anything.

The hoodlums screamed in pain as he set them all on fire, then he pulled himself up as they ran around and fell as ash. He picked up his broad-brimmed hat, covering his thinning hair and smoothed out his dirty coat. This was the sign. With the Holy Grail, he could wish for anything. He could get whatever he desired. No more, stooping to commoners. No more getting thrown out of bars. No more hearing people laugh at how far he's fallen.

This was his new beginning.

Bass Rankin smiled as he looked at his latest 'test subject'. She was certainly a pretty one, this girl. Long in leg, thin in body, and with blond hair. She was beautiful. Shame she wouldn't bend to his will. But at least he was getting more work done with his Crest Worms. They were a new discovery he got online, sold by some kid over in Japan. Feed them some mana, and they just kept growing and growing. And boy, did this girl have mana. And, he noted, her last moments seemed to be one of pleasure instead of pain.

"Bass." His mom knocked on his door. "It's dinner time." He sighed as she left. The experiments were self-functioning, able to go without outside interference. But think of all the notes he'll miss out on making because he was having dinner while she died. It was so stupid. He draped the curtain around the chamber, clocked it behind a spell, and then made himself less presentable. He knew what these dinners were for. He mussed up his hair and made sure it hung low over his eyes, before putting on some older, ruffled clothes. He then walked out of his room and greeted the guests for this week. It was a tall, older woman and her daughter, all braces and awkward looks. Stacy. He remembered her from school. Supposedly, she was as big a sadist as he really was. Well, he wasn't really a sadist. He was a sociopath. But he really liked it when his experiments caused pain, as long as he got notes from it.

"I'm sure you two know each other." Mom said happily as they looked at each other. They nodded, barely looking each other in the eye. "Bass has always been so lonely, I figured he could do with some company. Don't know why people don't like him though. He's such a nice boy." Maybe because they could see the real me, while you're stuck in a daydream. And maybe I don't have any friends because you gave me such a stupid name. But Bass was careful to hide all this behind a mask of boredom. It wasn't like he trained for it. Looking bored came naturally to him.

Dinner wasn't much of an affair. Mom and Mrs. Doughtry got along really well. Hell, Mom was always good at that stuff. You could put her in a room with a serial killer, and she'll be inviting him for tea next week and calling him pet names. Bass and Stacy just remained quiet as their mothers told all the embarrassing stories they could.

Eventually, dinner was finished, and Mom suggested they hang out in his room. This was the tricky part. If she really was a sadist, then she might like his work. If she wasn't, she might call the police. Hell, even if she was things might not go well. She might ruin his experiment just to cause the girl pain. He led her to his room, making sure to let her in first as Mom told him to do. As she entered, he noticed a strange red tattoo on the back of waist. Funny, she didn't look like a 'tramp stamp' girl.

"So yeah, this is my room." He said to her as he closed and locked the door. That was one thing he really wanted. "I don't really do much here. I'm a lab geek. Always wanting to know how the world works. But I hear about those rumours about you, and I wonder."

"You want to know if I really did kill my father." She said in her monotone voice. She was getting dangerously close to his experiment. If she noticed it, he was finished. "I did."

Oh. Well, that was one question answered. Maybe two if his hypothesis was right. "Any reason? Was he abusing you or something?"

"No. He was my toy. He'd pleasure me, make me scream. We always waited until Mom left. But he never really wanted it. I had to threaten him to get him involved." Ohh-kay. The school grape-vine was definitely. She wasn't weird. She was psychotic. Raping your own father? He suddenly felt worried for himself. "I smell blood. Are you working on people in here?" She looked at him, pulling a small dagger out of her dress pocket.

Ah, what the hell. It might keep her quiet, and leave him alone. "It's from an experiment. I found out magic is real. Only problem is, the only way I can use it is with these special worms, apparently." He pulled aside the glamour and the curtain to show the girl in the tank. "And they need to harvest from people. I found this girl casting spells the other day, and so I knocked her out and brought her here." Stacy just kept looking at her, her chest heaving in excitement. "They've been at it like this for a few hours. I think they work slowly to get as much power as they can from a single source." Anything else he was going to say was lost as she threw herself at him, kissing him wildly and passionately. He nearly struggled for breath as she started tearing at his shirt, before pulling away once she was done. As he panted for breath, he noticed she was looking at something on his chest. It was a drawing, showing a syringe in a sea of blood. At least, that's what the red colour made him think of.

"You've got one too." She said to him. "I got mine an hour ago, and I don't know what it means." She took her skirt and shirt off before turning around to reveal her tramp stamp. It was a bunch or jagged lines, set up in a triangle. Looking at them made him think of knives and sharp implements. But he didn't know what it meant.

"I think that if this girl has magic, then so does her family. Should've thought about that before. I remember where she lives. We can go there tomorrow, and interrogate anyone we find."

"And kill them?"

"Well, we can't let them live. They would interfere with our work." She looked at him a bit longer, before pulling off her underwear. Then she came back over to him, and pulled off the rest of his clothes.

Normally, a boy like him would enjoy this. But he was too busy thinking about what questions to ask tomorrow to care.

Angra Mainyu laughed as it found those two. Such wonders, such wonders. They will certainly spice things up.

Now he just needed to find the last three masters.

Well, there we go. This whole thing just came to me after I thought about how cool the Noble Phantasms of Servants were. And then I wondered what it would be like to give them to Ben 10. Like if he was Gilgamesh of someone, reborn in a new body. And so it evolved into this.

All the other masters are originals I've made for this story. I wanted a possible ally, a loser out for old glory, and at least one crazy master. I'm not too sure what the last three will be like, but I hope I get good ideas.

And as for there being 8 masters, well Ben would fit under an Avenger class when he's normal.

Oh, and yes. Bass is a shout out to Rankin-Bass.