This takes place the next day after 3x10 on Flash. And Barry didn't have nightmares about Iris' death yet. And the OC I have used in three other of my Fate/stay night fanfics.

And even though they are in anime, all the Servants and the Master from Fate/stay night and Achilles from Fate/Apocrypha look real-life.

When I saw the breaches in season 2, an idea for this story wormed its way into my head. Now I'm like "Fuck it, I'm going to make this story."

In the cortex of STAR labs, everyone except H.R, who called to say he would be late for some reason, was present. The rest were looking for metahumans. H.R. had just walked in, holding a tray of coffee.

"Coffee for everyone!" H.R. exclaimed with a giant grin on his face.

"When will your obsession with coffee end?" Caitlin asked with a sigh.

"It's not an obsession!" H.R. replied, happy mood not at all turned off.

"It kinda is," Cisco spoke up, not looking up from his computer screen. He typed something else on his keyboard. "I swear to God, it's all you ever drink."

"Well, that's because -" H.R. started, but Caitlin interrupted him.

"We know. It's because of the blight on your Earth. You've told us a million times."

Barry decided to save H.R. from this criticism. "So why did you get us all coffee and not just some for yourself?"

H.R. turned his smile away from Cisco and Caitlin and to Barry. "I thought this would be a way to welcome Julian to the group!"

"Did someone say my name?" Julian asked, leaning back in the chair to the desk in the next room.

"Why, yes indeed!" H.R. chimed as he went over to the man, grabbing a cup of coffee from the tray and handing it to Julian. "B.A. told me you normally drink it with a shot of espresso."

Julian took it, but didn't look away from H.R. "And this is tooo...what?"

"To say welcome to the group!" H.R. said happily. "After all, we're all friends!" Then he turned around and walked back to the others. "And here's some for the rest of you!" He began handing out a plastic cup for everyone.

"Well, I won't complain about free coffee," Wally said as he took his cup from H.R.

H.R. beamed at him next. "That's the spirit, Wally!"

Iris glanced at Barry. "I take it you already finished yours?"

"Uhh, yeah..."

Julian looked at Barry in shock. "How..?!" Then he remembered. "I swear, it'll take me time to get used to the idea of you being a speedster."

Barry walked over to Cisco. "Anything? It doesn't have to be a metahuman. Just a crime for Wally and I to stop."

"There isn't one," Cisco replied. "If there was, I would have said something by now."

"You bored, B.A?" H.R. asked.

"Well, yeah," Barry told him. "We've thrown Savitar into the speedforce, Julian's not being Alchemy anymore -"

"Doctor Alchemy!" Cisco said loudly.

"Whatever. And because of me and Wally, crime has gone down. So Joe and I are not needed at the CCPD as often anymore."

"As much as I hate to agree with Barry, he does have a point," Julian said, taking another sip of his coffee. "It is getting rather boring."

"OK, first off, you're the new guy, so you don't know what it feels like to go through what we normally go through," Cisco said, looking at him. "Until you do, don't be making comments like that!"

"Hey, hey! Calm down, Francisco!" H.R. exclaimed. "We're all friends here!"

"I know, but he's pissing me off," Cisco grumbled.

"Now you know how I feel every day working with him," Barry muttered to Cisco.

Cisco didn't look up from his computer screen. "Barry, now I know what you mean by 'I hate working with that guy'."

Barry sighed and leaned forward on the desk with the computers. "No, you don't. Trust me. You haven't seen anything yet." There was a beeping sound on Cisco's computer. "What's that?"

"Someone's coming through a breach here!" Cisco replied.

"What?!" Barry exclaimed.

"Where are they coming from?!" Joe demanded.

"Don't know! Let's head to the breach now before we're too late!" Cisco said. The group of eight ran down to the breach room, though Barry and Wally used their speed to get there first in case troublemakers were coming. Shortly after everyone had entered the room, the blue breach opened.

"Who's coming?!' Caitlin demanded.

"We're about to find out," Barry replied. Julian had questions, but decided to leave them for later. This was probably more important. Joe had his gun out and at the ready in case trouble was coming.

Two people came out of the breach and hit the floor hard. One was holding another bridal-style, so when they fell forward, that person was now on top of the other.

"Get off me!" the one on the bottom shouted.

"Sorry!" the other apologized. The person who said sorry was a man. As he quickly got off the other, the rest could see that he looked young - probably in his 20s. He had green hair. While the hair on the lower half of his head looked short and dark green, the hair on the top of his head was a light green color. It was also a little longer and spiked and some was hanging down and covering most of his left eye. His eyes were light brown. He wore an orange sash wrapped over his right shoulder and around his left hip. It was over plating, which probably had chain or scale mail in the fabric, over his chest. And this was over a black short-sleeved shirt that looked to be made of thick fabric, but not wool.

On both of his shoulders were steel shoulder armor. And at the bottoms of them over the arms were silver-grey squares of fabric. On his hands were black gloves with the sleeves of them going past halfway up the forearms. Connected to a steel loop, one at the end of the sleeve of the gloves and one at the wrists, were steel pieces of armor.

He wore a belt of steel plating and below were black pants covering his legs. He was wearing steel boots. At the ankle up to his knee was twisting metal, two lines looping in on each other.

The other person got up, grumbling and dusting themself off. It was a woman, looking to be around the same age as the man. She had silver hair going down her back to almost her waist. A couple strands of her bangs were getting into her bright blue eyes.

Unlike the man, she wasn't wearing any armor. She wore a long-sleeved black button-up shirt under an opened light blue jacket. Over her legs were a pair of blue jeans and on her feet were what looked like shin-high black boots over her pant legs.

But what was really interesting was the back of her right hand. It looked like a red tattoo was on it. Near her wrist was a shape like a U going up to her fingers, but with a gap in the bottom of the shape. And on the outside of the two line was what looked like only one row of feathers. But the tips of them were pointed. In between the two lines was what looked like a red outline of a diamond.

The girl stopped grumbling and looked at the group of seven staring wide-eyed at the group. "...Rider?"

"Yeah?" the man, Rider, replied.

"Where the hell are we?"

"Like I would know." Then Rider looked over his shoulder, where the breach had been. It had closed as soon as the two came out. "It looks like we weren't followed by the Alters."

"Umm..." Cisco started, making the two strangers look at him. "I'm sorry, but who are you two?"

"We don't have to answer," the woman replied. "We just want to know how to get back. Screw the Root, I just want the Holy Grail right now so I can wish the problem away."

Barry was suddenly in front of the woman. But she didn't look shocked at his speed, as if she had seen someone go that fast before. He grabbed her left arm. "Sorry, but unless you want us to lock you both up, you'd better answer our questions."

Then Rider did something that surprised the group, but the woman was unfazed. He held his right hand out in front of his body, fingers out and palm facing out. What looked like a thick bolt of green lightning appeared in his hand. He closed his fingers around the lightning. As soon as he grabbed the bolt, the green faded. He was now holding the black shaft of a spear, horizontal to his body. At the end in front of his left shoulder was the blade of the spear. The blade was blue. And it was shaped like an upside-down T. The main point was bladed on both sides while the two "branches" were only bladed on the edge facing up, in the same direction the middle of the three blades was pointing.

"Whoa!" Cisco exclaimed. "That guy's suddenly got a weapon!" Joe just tensed his finger on the trigger.

Rider ignored Cisco. The man was snarling at Barry. "Unless you want to lose your arm, release my Master right now!"

"Stand down, Rider," the woman said, not taking her eyes off Barry.

Rider glanced at the girl and opened his mouth, like he was about to protest. But then he closed his mouth and lowered his right arm, his spear vanishing in a dust of blue particles. He sighed heavily. "Whatever you say, Master." Joe sighed and lowered his gun slightly, but still held it with both hands, at the ready.

Julian spoke up. "Why does he keep calling her Master?"

The woman spoke, still looking Barry in the eyes. "You don't seem to be a normal human yourself. Unless everyone from this place can move that fast."

"Nope," Caitlin told her with a sigh. "Only he and Wally can do that in our world."

The girl continued talking. "In that case, it should be fine if I tell all of you this. To answer the question that had been asked first, my name is Akiko Hashomoto." Barry let go of Akiko's arm and she gestured to her green-haired partner, who was crossing his arms and giving Barry a dirty look. "I am the Master of him, a Rider-class Servant. As such, please call him Rider."

"And why are you two here?" was Iris' question.

Akiko looked at her. "It's a long story."

"It doesn't matter; tell us anyway," Barry said to the stranger. "We need to know if we've been pulled into a new situation."

Akiko sighed in defeat. "Ugh, don't say I didn't warn you."

"Why?" Cisco asked.

"We also have to tell you about the events leading up to now," Rider broke in, answering Cisco's question. "Namely, about the Fifth Holy Grail War."

"Wait, are you talking about the Holy Grail?! The cup used by Jesus during the Last Supper?!" Cisco exclaimed.

Akiko nodded. "Yes, the very same."

"And you mentioned a 'War'," Caitlin added. "What does that mean?"

"Exactly what it sounds like. It's a series of battles for the possession of the Holy Grail, able to grant any wish of the winning pair," Akiko told her.

H.R. had his arms crossed in thought and was currently tapping his right arm with one of his drumsticks. "Wait, the winning pair? So you're in teams of two?"

Julian was glancing at everyone he knows. "Do you all follow this? Because I don't."

"If we did understand the whole situation, we wouldn't be asking questions," Caitlin reminded him.

"Right..." Julian murmured.

"Don't worry; I'm lost, too," Joe whispered to Julian.

Barry continued the interrogation of the two breachers. "So...Akiko, right?" Akiko nodded at Barry and the man continued. "What's the 'Fifth Holy Grail War'?"

"It's called the fifth because it's the fifth time a war for the Grail broke out," Akiko said. "I'm what's known as a mage, someone who can manipulate mana, the energy inside everything and all around us, to cast spells."

"So you're saying you're a magician?" Cisco asked.

Caitlin looked sharply at him. "Those might not even exist where she's from! If they don't, she won't have a clue what you're talking about!"

"No, they do exist," Akiko replied. "But the spells mages can cast are...different." To show them what she means, she held out her right hand. A ball of fire formed in her palm briefly before it went out. "That was a low-quality spell, too. I could go large-scale, but I highly doubt the rest of you would get away unscathed."

"It's cool that you can do tricks like that!" Cisco exclaimed. He looked at Rider. "Is he a mage too?"

"No," Akiko told him. "He's a magical entity, a high-class familiar known as a Servant."

"A Servant?" Iris echoed, cocking her head.

"A Heroic Spirit. In other words, a hero from either history or mythology."

"Did this just turn into some sci-fi scenereo?! Joe exclaimed, lowering his gun down to his side.

"Wait, so he's a hero from the past?!" Julian demanded.

"Yes. Heroic Spirits are souls of heroes from the past, present, or future. Seven mages are chosen by the Grail to fight in the War for it. They are called Masters. Each summons a Heroic Spirit, or Servant, to be their partner in the War. And each of the seven Servants are summoned into one of the seven classes. They are Saber, Lancer, Archer, Rider, Berserker, Caster, and Assassin. Now for the details about the War itself.

The seven chosen Masters fight to the death in a series of battle taking place in Fuyuki, Japan. These fights pit Servant against Servant. And for the Servants that are killed, the mana making up their bodies is fed into the Holy Grail. The mana of six Servants fed into it makes it able to grant any wish. Servants are crucial because only they can touch the Holy Grail, as the Holy Grail is also a spiritual entity. When only one Master-Servant pair remains, the Grail can be claimed and the winning Master and Servant can have one wish granted.

However, Servants aren't the only things crucial. A Master is crucial to a Servant being able to stay in this world. Servants need mana to keep their physical forms. The Master that they have a pact with gives them the necessary mana. And if a Master is killed, the partnerless Servant has only a couple of hour to make a pact with someone chosen by the Grail, but without a Servant, before their mana runs out and they vanish."

"So, basically, this Holy Grail War is one big bloodbath," Joe summarized.

"If that helps you understand, then yes," Akiko said to him. She then held up her right hand and presented the back of it to the others, showing them the red tattoo-like marks on it. "These are my Command Seals. Each is made up of three strokes."

"And since command is in the name, I take it they have something to do with orders?" Cisco guessed.

"That's right. If you want to force a Servant to do something against their will, to make them teleport, or to grant them more mana without a mana transfer, you use a Command Seal. However, only three strokes are granted to you for the whole War. And once you use your last Seal, you are no longer a Master." Akiko lowered her hand. "Rider and I get along well, and I don't have to force him to obey my orders. So I have not used my Command Seals yet."

"So, tell us why your here," Barry said. "Or is there more overview?"

Akiko shook her head. "No. I covered the basics, what you all need to know. Now for why Rider and I are here. Rider and I, plus Saber and her Master, were the only ones left in the War. So the Holy Grail appeared, but would not be able to grant wishes without a sixth dead Servant's mana. However, the Archer from the Fourth War was still in the world for some reason. He planned to use the Grail to wipe out the entire human race. So we four went to Ryuudou Temple, where he and the Grail were, in order to stop him.

We knew it was a trap. He needed to kill just one of the remaining two Servants to activate the Grail. But Grail Mud was coming out of the Grail, which had not been summoned properly. The mud is curses that have taken physical form and sets fire to whatever it touches. To prevent the mud from burning down the entire city, we decided to destroy the Grail. We took the Archer down and Saber used her Noble Phantasm, a Servant's ultimate attack, to destroy it. But when she hit hit, her Noble Phantasm cut the Grail open and mud flew out. Saber's Master was hit and was killed. Saber was also hit, but she...changed. She took a...darker form. She became what is called an Alternate Servant."

Cisco cocked his head in confusion. "An Alternate Servant? What's that?"

"An Alternate Servant, or Alter for short, is a corrupted Servant. They lose their sanity, but also gain a boost in power. And they don't need Masters. They are able to generate their own mana. Now back to Alter Saber. She somehow managed to revive the five Servants that had already been killed, plus the Fourth War's Archer. All were now Alters.

Now since the Grail was destroyed, Rider should have vanished. But he didn't. And that means the Holy Grail War is still going on. Saber must have taken in a piece of the Grail when she was hit with the mud. And the only Servants left are her and Rider. But Saber has control over the other Alters. And she's hunting Rider down to kill him and win the War.

And that's why we're here. We managed to kill Alter Caster and Alter Assassin, but Alter Saber, Lancer, both Archers, and Berserker are still left. When Saber destroyed the Grail, it created a rip in the fabric of space. Rider and I didn't bother to see where it led. We were focused on fleeing the Alters. Eventually, they cornered us and we fled to the rip, hoping it would be a way to escape the Alters for now."

"It was her idea!" Rider put in. "We didn't know what it did, so I tried to convince her otherwise. But she said we should risk going into the rip. If we didn't, the Alters would slaughter us."

"And one other thing," Akiko continued. "One of Rider's Noble Phantasms grants him invincibility to most of his body. However, special cases can bypass this. One is what the Noble Phantasm considers a 'friendly act'. For example, a bite from a vampire could get through, as it can also be seen as a way to make a comrade of the victim. Another way is a skill called Divinity. Rider has C-rank Divinity. Any attacks delivered by a Servant with this rank of Divinity or higher will wound him. Those with D or E-ranked Divinity can also wound him, but the power of the attack is reduced.

When the Servants became Alters, only three had the Divinity to wound Rider. But the mud gave those without Divinity C-rank Divinity, which would explain the increase in their power."

"So now any one of them can hurt Rider?" Joe summed up.

Akiko nodded. "Yes, but like I said, two are already dead. So five Alters remain. Now that I've answered your question, why don't you answer one of mine. Where are we?"

"Well, this is Earth-1. You two are probably from another Earth in the multiverse," Cisco said.

Julian snapped his head to look at Cisco. "The multiverse?! So these two came from a parallel universe?!"

"Wait, I'm not following!" Akiko exclaimed.

"Basically, you two went through a breach and landing on an Earth that both is and isn't the one you're familiar with," Caitlin explained.

"Well, get us back!" Akiko shouted.

Cisco scratched the back of his head sheepishly. "Problem: without knowing the Earth you two are from, we can't send you back."

Akiko felt like someone hit her with a sack of bricks. "...So you're saying we're stuck here?!"

"Just until we calculate what universe you two are from," Cisco replied quickly. "Until then, both of you have to stay here."

Akiko facepalmed. "Fantastic..."

Barry turned around to look at Cisco. "They can use the room that Jessie and the Earth-2 Harry used." Then he looked back at Akiko and Rider. "That's right! You should probably learn our names. I'm Barry Allen."

"Cisco Ramon."

"Caitlin Snow."

"H.R. Wells."

"Julian Albert."

"Iris West."

"Wally West."

"Joe West."

"And our room?" Akiko prompted.

"Oh, right! Right this way," Cisco said, gesturing to the hall. He took the two to a room next to the breach one. After he did, he closed the door behind the two when they entered. Akiko flopped down onto the bed while a mist of white dust, mana, enveloped Rider. It blew away like a wind had come off of Rider's body and the mana vanished.

Rider was no longer wearing the same clothes he had before. He was now wearing an orange shirt under an opened black jacket. Over his legs were a pair of blue jeans. He also wore a pair of black shoes.

"Akiko," he said.

"Hmm?" Akiko sat up in the bed, looking at her Servant. "Something wrong?"

"Maybe. Did you really have to give them that many details?!"

"I had to in order to gain their trust. Besides, we're stuck here. I had to tell them everything in order to get their help."

"Well, at least you didn't tell them my true name."

"Don't worry, Achilles. We may have gotten their trust, but they haven't completely got ours. Until they do, we'll keep that one little secret."