So yeah despite the promises to update my other stories first (which I really suck at keeping, so very sorry for that by the way) I went and came up with this idea: a Fate/Stay Night and Tokyo Ghoul crossover where Kariya summons Kaneki during the Fourth Holy Grail War under the Berserker class. I like to think its believable since the two of them have such similar backgrounds. Imagine my surprise when I learnt that NOBODY has actually done a mix between these two awesome animes before. It kinda feels nice in a way that I'm the first to ever do a crossover between two series. Just to be CLEAR: in this story the worlds of Fate/Stay Night and Tokyo Ghoul are the one and same since I can actually get away with it.

Will be rated M (Tokyo Ghoul said enough) with lots of violence, mature language, graphic descriptions and mature themes. If some new stuff gets added later in the story I'll post a warning at the start of the respective chapter. If such stuff offends any of readers then don't read it (or do if you don't care). Fate/Stay Night belongs to Type-Moon and Tokyo Ghoul belongs to Ishida. I own nothing.

Try and sue me now lawyers!

Enjoy.

As he chanted the incantation for the ritual made to summon a Servant, Matou Kariya grimaced in pain as the Crest Worms moving beneath his pale skin made their presence known to their host. Thanks to the light emitting from the circle drawn in animal blood by Zouken, Kariya's fragile health was well illuminated in the same dark room where he had suffered many times throughout the past year.

However, he had not regretted the choice he had made, whereas most others would have given up after the first day had they been in his position. Still, it had been extremely difficult making it this far. If not for the love that he held for the little girl that he loved as his own daughter and the hatred that he possessed for both Tokiomi and Zouken he probably wouldn't have made it here.

Even now, Zouken's disgusting grin reminded Kariya of how completely and utterly satisfying it would be to kill him when the time came. To crush him into paste under the foot of his powerful Servant. The old vampire standing in the corner was just as responsible for Sakura's situation as Tokiomi was.

"Remember our deal, Old Man. I fight the Holy Grail War for you and win you the Grail. In return, you'll release Sakura back to her family."

Saving Sakura would come first, of course. Then he would seek revenge, even without a Servant if he had to.

Kariya's decision to get his hands on the Grail in exchange for Sakura's freedom was one that he knew he had to make on his own. As much as he hated to admit, he had nearly nobody in the magi community that he could rely on to support him in his endeavour. Though Aoi would almost certainly be willing to help if she knew of his plans and what was happening to her daughter, Kariya simply loved her too much to involve her in this. It would be far too dangerous for her and in the event that he didn't make it Sakura would need someone who cared genuinely enough to look after her. This left basically nobody else. Byakuya was a useless drunk who resented his brother while their 'father' was a horrifying abomination who hated them. The less said about Tokiomi the better, leaving him with only Zouken to somewhat rely on.

He would win the Holy Grail. He would not lose.

He couldn't afford to, for Sakura's sake.

Of course, Kariya wasn't stupid enough to believe that the wrinkled monster was trustworthy. Zouken made no secret that he enjoyed his son's suffering so it made sense that he might not live up to his end of the bargain just so he could prolong the suffering of both Kariya and Sakura.

Which was why Kariya had refused the catalyst that his father had found for him. While not an expert on summoning, he knew the basics concerning the bringing forth of Servants and therefore knew that a catalyst was not completely necessary. His choice had left Zouken temporally startled and angry (points for him) but he had accepted his decision eventually, probably most likely just to see what kind of Servant he would summon without the aid of a catalyst. This way Kariya would hopefully summon something that would be more suited for him.

Even as the veins visible under face became more pronounced, the Matou continued reciting the incantation he'd memorised from Zouken. Even as the earth underneath his feet began to vibrate and he reached two lines that would add the Mad Enhancement, he pushed ahead. Out of the corner of his eye, he noticed the other room's occupant smirking as he added the extra words to the ritual.

'For Sakura.'

As reached the final line, Kariya resisted the urge to cry out as the agony he felt increased as the worms fed on his body. Anger clouded his mind, numbing the pain. With a great shout, he finished just as the dark basement was consumed by white light.

Come Forth!

Kariya quickly collapsed on the ground in a heap, barely remaining conscious from the severe strain of the summoning. Wincing as more pain assaulted his already battered body, he allowed himself a small pat on the back as he coughed up an unhealthy amount of blood at his feet. He had done it. Despite the present agony, exhilaration bubbled in the pit of his stomach like a boiling pot. Breathing deeply, he tried to see through the evaporating smoke with his one remaining good eye, his other one staring to the side uselessly as the brightness in the room quickly diminished.

After several long seconds with most of the smoke gone, even with deteriorated eyesight, Kariya soon got his first proper look at his Servant. From where he sat, he was able to make out a dark humanoid outline with a head of white, along with some sort of dark covering hiding their face. While not overly bulky, the shape of the body identified it's gender as male.

Finally the last of the smoke cleared.

"Oh, what is this?" An ancient wizened voice asked mockingly, but also with an undertone of curiosity. The voice was followed by the sound of footsteps and a cane tapping the ground as the wielder went to get a closer look. "What have you summoned here Kariya?"

The two of them ignored the room's other occupant, both apparently preferring to examine each other. The one standing eyed the other's hair before locking eyes with him.

The Servant regarded Kariya with piercing grey eyes, staring out from beneath long locks of pure white hair. The Master idly noted, much to his surprise, that they were full of intelligence and willpower, completely lacking any sort of madness. Under the eyes, a torn red scarf wrapping around the head hid the wearer's nose and mouth from view. He wore a sleeveless black bodysuit under a matching cloak that had certainly seen better days, covered in grime and what suspiciously looked like blood. The Servant managed to cut an intimidating figure despite being only average height, holding himself lightly on his feet as he regarded the man on the floor almost like a leader sizing up a potential ally . . . or a predator sizing up a meal.

Kariya couldn't help but wonder if this was actually a Berserker that he had summoned.

Berserkers were supposed to be insane after all.

He grimaced as a fresh wave of pain hit him. Damn worms.

The Servant raised a hand to pull away his scarf. As the hand gripped the cloth, Kariya was startled by the colour. Instead of any of the normal shades that were associated with normal unblemished human skin, the hand seemed to be made up of finely woven patterns of what appeared to be raw crimson flesh, complete with razor sharp talons at the end of each finger. Kariya looked down and saw that it continued until reaching the elbow where normal skin and flesh was shown on his Servant's bare arm. He checked the other arm and saw that the same applied to the left limb as well, both being well muscled.

As the scarf was pulled down, Kariya got his first look at his Servant's face and was surprised at how young the stoic face looked. No older then twenty-three or twenty-four at the very most.

"I am Servant Berserker of the Fourth Holy Grail War. I ask of you: are you my Master?"

The question went unanswered as Kariya broke out into another coughing fit even while his mind whirled in confusion at the fact that he had summoned Berserker, one who retained the ability to speak.

Hoping to make some sense of all this, he looked up the Servant's stats and was pleased with what he found.

Perhaps he had made the right choice to not accept the catalyst after all.

"Umm . . . yes I am. M-My name is Matou Kariya," the effort required to speak taxing on the man's fragile strength. "I am your Master for this war Berserker."

Berserker nodded. "Good, the contract is established then. There are matters that we must discuss, but first . . . please wait a moment."

He stopped, voice trailing off as he looked to stare at the floor. He was silent for several moments and then suddenly stark black energy appeared, completely encasing him from head to toe. Violent tendrils of bright electricity lashed out, startling both Kariya and Zouken as their ears were assaulted by what sounded like a miniature hurricane, the weaving patterns illuminating the room. The strange anomaly continued for another few seconds before calming down. It then disappeared, revealing Berserker again.

Different from before.

Berserker had shrunk, going from a young muscular adult to a skinny teenager, de-aging at least five or six years. The hands and forearms were no longer of that odd material and were shorter and thinner as well. Kariya noticed that the attire had changed as well, replaced with a similar but notably different bodysuit with cutouts. His face was also hidden once again, this time behind a black leather mask and eyepatch that probably would unnerved him in another life had he not been the son of Matou Zouken. With its lipless mouth and snarling gnashing teeth, it resembled something right out of a horror film.

"Sorry about that." Berserker chuckled as he rubbed the back of his head, ruffling his hair, sounding almost sheepish. His voice was younger and less deep, like that of a male only in his teens.

Kariya stared at his Servant, unsure of what to make of this.

Frowning, he checked to see if anything was wrong with Berserker.

He gaped.

Berserker's stats had somehow changed.

Class: Berserker

Master: Matou Kariya

True name: Kaneki Ken

Titles: Eyepatch, Centipede, Black Reaper, One-Eyed King

Alignment: Chaotic Good

Sex: Male

Height/Weight: 170 cm 58 kg

Current stats (Eyepatch):

Strength: B (B+)

Endurance: B (B+)

Agility: B+ (B)

Mana: D (D+)

Luck: D (E)

Noble Phantasm: A++

() indicates use of Mad Enhancement.

Class Skills:

Mad Enhancement: E: the signature skill of the Berserker class, raising basic physical parameters in exchange for hindered mental function. If low enough, the user can retain their sanity and enter a temporary madness when they choose to.

Self-Replenishment: C+: allows the user to self-produce and store their own mana inside their body. A requirement for this is the consumption of flesh of humans or ghouls.

Personal Skills:

Battle Continuation: A: a ability that allows for the continuation of combat after sustaining mortal wounds. It will also reduce mortality rate from injury. This skill represents the ability to survive and/or the mentality of one who doesn't know when to give up.

Eye of the Mind (False): C: a natural talent to avoid danger on the basis of an innate sixth sense, intuition, or prescience, where accuracy of instinct has been augmented by experience or by constant exposure to danger.

Mental Pollution: D: due to possessing a distorted mentality, it is highly improbable to come to any sort of understanding with individuals that do not possess an equivalent rank of Mental Pollution. It is also possible to shut out any sort of mental attack, including mental interference Thaumaturgy.

Noble Phantasm:

Unknown: (Support) A++ (something that allows Berserker assume any identity that he has ever been renowned for in his life. Each identity has their separate own stats, class skills and personal skills. Shown to have two identities so far. The more powerful the identity, the higher the mana cost).

If you are all wondering why Kaneki changed from his older self to his younger self, you'll find out in later chapters.

Hint: Its related to his Noble Phantasm.

I cannot promise that this will be a good fic or that I will manage to finish it. I am struggling so much with my other fics at the moment, unsure about where to go since I rarely write a story where I have the entire plot planned out ahead. Writer's block is a bitch and I know this better any anyone. Until next time then.