The Overlord of Mysteries

Hello, this is my first time writing a fanfiction. If you notice any errors, please feel free to give me constructive feedback. English is not my first language, so if you notice any mistakes, please mention them in the comment section at the end of the chapter. Let's begin the story!

Word Count: 4400 Words

Note: Just a reminder that I've changed the Guild Auxiliary chapter. I've made some changes to it. I've removed a couple of NPCs and added a few.

-----------------------------------------------------------

Fate Stay Night, ??? [Bit of AU]

The Holy Grail War is a war between mages fighting for the Grail. The Omnipotent Chalice was said to be able to grant any wish to the winner.

In a Holy Grail War, the Grail chooses Seven Masters who are mages. Beings with Magic Circuits in their Bodies that produce Mana. Though not all beings have Magic Circuits, Mana Beast, Dragons or Gods have their Mana Core that produce Mana for them or Divinity in some cases.

The selected Seven Mages summon Heroic Spirits to act as their Servants from the Throne Of Heroes. The Heroic Spirits are Heroes or notable figures from the past or the legends taken form.

Some of the notable summons or the Heroic Spirits from the current and past Holy Grail War would be Gilgamesh the King of Heroes, Artoria Pendragon aka Arthur Pendragon the King of Knights, Hercules, Iskandar the Conqueror, Solomon the King of Mages, Cu Chulainn the Son of Light, Medusa and many more.

In the war, the Masters with their Servants fight one another for the Grail. After all the Seven Servants are summoned the Grail manifests in due time. But it remains incomplete until only One Master and a Servant remain. By killing the rest of the Masters and Servants only will one be worthy to hold the Holy Grail. Sacrificing the rest to the Grail.

The winner gets one wish of theirs granted by the Omnipotent Wish Granting Chalice.

The Holy Grail War has taken place four times before the current one. Usually, the Holy Grail War happens with long intervals between each consecutive war.

But unlike the previous wars, the current war. The Fifth Holy Grail War was taking place with a mere 10-year gap.

There exist three major families overseeing the Fuyuki Holy Grail War except for the Church and the Mage's Association.

The Tohsaka, Matou and Einzbern family. Einzbern mainly dealt with the Homunculies, Tohsaka could be considered the most normal family among these.

Whereas Motou struggled with the lack of candidates for inheriting their family. While the Old Man a worm, the Master of the House and the Family, lurked preying upon his family heirs for the Holy Grail.

Though they lacked candidates as their heirs were born without Magic Circuits, they blamed it on the Magic Lines of the City not being compatible with them.

The Matou family was originally from the region that is now in Russia and had sought shelter in Japan a couple of centuries earlier.

It was all for him to become immortal. Zouken's wish to become immortal has driven him to covet the Holy Grail.

Training young mages of his family to win him the Holy Grail.

Failing as they were, the Matous' turned towards Tohsaka. After all, Tohsaka had gotten two daughters both gifted in magic.

After making a deal with Tokiomi Tohsaka, Zouken Matou succeeded in securing his family an heir.

One of the two daughters born to the Tohsaka family, Sakura had been adopted by the Matou family.

She had been raised by Zouken to become a capable mage. He had raised her to become a Master in the Holy Grail War. He had trained her with the worms to be a strong Mage. He had implanted worms in her to get the results he wished.

There had been an instance in the previous War where Kariya Matou a friend of Sakura's Mother and also Sakura's half-brother Shinji's uncle had proposed a deal to Zouken to free Sakura in case he won the War.

He had been the Master of the Berserker and had fought in the last war to be only killed. He was also one of the last of the Matou family to have Magic Circuits.

He sacrificed his life and it was all in vain.

He died a dog's death in an alley.

----

Sakura Pov [5 Years After 4th Holy Grail War ]

It was the same as every day. I woke up in the Matou family manor as their adopted daughter.

I still dream of my past. My father, mother and sister. Though I fail to remember the Moments I had with my Father and Mother sometimes.

I still remember the games I used to play with my sister. I even see her daily. We both go to the same school.

I hate it.

I suffer day in and day out, being tortured. While she lives her life without a care in the world. Enjoying her life with Mother and Father.

---

She hated it.

Despite the difficulties, she still has a haven in all this.

She used to hate her now she is unsure. She knows that her father died ten years ago and her mother also died a few years ago.

---

General POV [Present Time]

Though they both are dead now. She still envies her sister. She didn't come to save her nor did her Father and Mother.

There wasn't a day where she didn't call for them while being trained by Zouken Matou.

Being trained by the worms, was torture for her.

It didn't take long before she got adjusted to her new life.

Though she still wasn't there, her half-brother wasn't the kindest person. He beat her tortured her and also sexually assaulted her. He had crossed the line in doing so.

But there was still a ray of light, a figure of hope in her life.

Shirou Emiya, her school senpai. Who also happens to be a friend of her brother.

He was someone who cared for her and, looked after her. They both were in the same club.

Just like this, she lived through her life. Went to school in the morning, practised archery after school and then visited Shirou's home after school. Later at night, she returned to her home.

Until one day where she was tasked with participating in the Holy Grail War. She was asked to summon a Servant in-order to fight in the Grail War.

Unbeknownst to her it was Zouken who worked on the Command Seals or Command Spells used in the Holy Grail War. He had initially planned to use Sakura to summon the Servant and then transfer those Command Seals to a NoteBook using the crest worms for Shinji to command.

Though he deemed Shinji to be a useless mage. Yet he was his heir.

---

Sakura Pov

I was told to come to the underground chamber after returning from school.

Before the ritual, I was tasked to also come to the magic chamber. I hated it when those worms entered my body.

I hated the feeling as those worms entered my body.

It was training for me to become a mage but it was suffocating.

I walked into my room after the training. I walked carefully to not run into my brother while on the way to my room.

After opening the door, I made my way to the bed and sat on it.

It was 11 PM and I was told to come at midnight to the underground chamber. I still have an hour to myself.

I sighed as I lay down on my bed.

I wonder what Shirou Senpai is doing? I couldn't go to his house today to cook him dinner. I wonder if he had dinner...

"Huh!"

I rested for a bit to relax my body after the training. Now only ten minutes remained for the assigned time.

I got up from bed. As I was making my way towards the door I observed the deck of cards lying on the table.

If I am not wrong they are called Tarot Cards. I got it from a Senpai at the Archery Club.

She said that it was used for Future Reading.

From what I heard the Senpai had suddenly gained an interest in horoscope.

It's a gift she brought for me from her tour. She gave one set of it to everyone in the club.

I wasn't able to have my horoscope read, but I wonder if this is also magic. Does this work similar to magic. Should I give it a try anyway.

So it's something like this.

You take the deck shuffle the cards and place them all on the surface with their back facing us.

Now you should pick a card, well that's what she said.

I shuffled them up and placed them all on my table.

Now to pick one card.

I picked it up and turned the card to see its contents.

It was The Fool.

But I am not sure what this means. I should have asked Senpai when she gave it to me.

It is a unique card.

I stared at the card as I made my way to the door.

I walked out of my door and was on my way to the underground chamber when my brother came out of his room.

I hid the card in my pocket to hide it from him. Had he seen it, he would have gotten angry.

He was already angry with others in the club for his reading. Senpai did the Tarot Reading for everyone in the club and brother couldn't wait his turn and forced his way to draw the card.

He got the Death Card if I remember it right.

After the reading, he had a burst of anger on the cards and Senpai wasn't able to continue with her reading.

It was also because of this that Senpai couldn't read my horoscope.

"So Sakura. I've heard that Grandfather has called you to the Magic Chamber."

"Yes Brother"

"Good. He has also called me to come. Let's go."

"Yes"

After the agreement, he led the way as I followed behind him to not anger him unnecessarily. I shouldn't remind him of the exchange back at the school.

We were silent for the most part as we walked but right before entering, he turned around.

"Just because you have Mana doesn't make you superior Dim Witt. Don't forget that I am the true heir to the Matou family while you are just a Mana Battery. Your only purpose in life is to serve the Matou Family till your death. Just don't forget your place."

"Yes, Brother."

"Good, now let's go. We can't keep Grandfather waiting. Just make sure to know your place."

Soon after speaking his mind, he walked into the chamber and I followed behind him.

The chamber was dimly lit, with a giant magic circle drawn on the floor. The head of the Matou Family stood a bit distance from the Magic Circle.

The Chamber had a lot of shelves filled with potions and items and bookshelves filled with ancient books.

I've been here before. Right across that bookshelf is a hidden room. Grandfather had once taken me there after the session with the insects and worms.

I've seen Grandfather go in and out of it multiple times. From what I have seen it is filled with old books and scrolls. Though I am not allowed to enter it.

But I am not sure if Brother is allowed to enter or if he knows its existence.

Right now, the door to the secret room was partially open. Grandfather must have forgotten to lock it.

"Shinji step aside, maintain your distance from the circle."

"As you say, Grandfather."

Grandfather instructed us on what to do as soon as we stepped into the room.

Grandfather upon seeing us, first instructed Shinji as he turned towards me.

"Sakura, today you will be summoning your Servant. For the Holy Grail War"

"Yes, Grandfather."

"I've prepared an item to be used as the catalyst for the summoning."

"Tschh"

As Grandfather was explaining about ritual and the requirements with relation to mana and the requirements of the mage, I heard Brother click his tongue in annoyance. It was inaudible. Though Grandfather heard it, he brushed it off. Not bothering about it.

I moved in front of the Magic Circle and got ready to perform the summoning.

I repeated what Grandfather had taught me previously. The only reason he repeated the agenda after our arrival was to remind my brother and me about what was at stake here. He didn't have to recollect the information he had given us again and again.

As I stood in front of the Circle, Grandfather stood beside me and handed me a piece of cloth.

"This is going to be the catalyst for your summoning."

"Yes"

"Now start it."

"Heed my call..."

I had started my cast for the ritual, I repeated everything Grandfather had asked of me. As I was at the end of my cast, the Magic Circle was glowing and strong wind blew in all directions despite there being no opening in this chamber for wind to come in from outside.

'Magic is fascinating and dangerous. It is also cursed.'

My eyes wandered to Grandfather while casting, I was trying to gauge his reaction to make sure I was not making any mistakes.

I could not afford to mess up. I did wish to go to the worm room again.

Grandfather had the same face when I showed up, I am nervous as it is. I shouldn't mess up.

It was the same emotionless face that he always had. At the same time, I saw my brother from the corner of my eye. He was making it, the same face whenever he was angry at me. Whenever he wishes to punish me.

I messed up, the mana I was trying to build up and transferring to the circle got disrupted.

I messed up.

It was only for a fraction of a second but when I saw my Brother's face, I got distracted.

Lightning zipped around the Magic Circle and strong winds pushed me back. I ended up falling on my back.

The Magic Circle went haywire.

I got up to look at Grandfather, he was looking at me with a frown. I should have been careful.

My brother was standing right behind Grandfather but now came forward. He stood to my left.

I could see his smirk.

He was happy that I messed up.

Grandfather tried moving towards the circle but the strong winds and the small lightning that streaked around the magic circle pushed him back.

Yet he tried cutting through the wind but the mana flowing in the circle pushed him back.

I had truly messed up. Now I won't be able to visit Senpai tomorrow.

I saw my brother smirking while looking at me. I looked down to see my clothes in tatters. Brother was someone without magic. I could understand his frustration seeing me. A nobody, from his perspective I must be seen as someone trying to steal his limelight and family.

Despite the mana fueling it being cut off, the magic circle was still going strong. Grandfather stood up and watched the circle with interest from a distance.

I was the closest one to the magic circle, with my brother standing an arm's length away to my left. While Grandfather stood to my right but was a few feet away from the circle.

It might be because I was the one standing closest to the circle. After all, I saw The Fool card lying at the centre of the Circle.

It might have fallen off when my dress got torn off.

The Magic Circle suddenly went silent. A strong wind blew towards us, forcing me to close my eyes.

When I opened them, I was shocked to see a Man sitting cross-legged on the floor upon the Magic Circle.

I had summoned someone. It was surprising but I still had the catalyst that Grandfather gave me. Though in the mana maelstrom, it had fallen off my hand. Also due to the spell failure, I wasn't able to use it.

I looked around to see it lying at the foot of my Grandfather. I saw it, Grandfather had an expression of shock. I guess he couldn't believe that the ritual worked.

I looked to the left to see my brother looking at the magic circle with shock. Noticing my gaze he turned towards me with a look of contempt.

I was scared, not willing to look him in the eye any longer I turned towards the Magic Circle.

The Young Man was someone who looked to be in his early twenties or maybe late teens. He was wearing a suit with a hat and there was also a cane beside him.

Not much time had passed since the summoning but he hadn't opened his eyes yet.

I was nervous thinking of the consequences of it.

I looked to the side to see that Grandfather had recovered from the shock and was looking at the man with a scrutinizing gaze. While my brother was looking at the man with contempt. He was also smirking at him. Maybe hoping for the summoning to be a failure.

I stepped forward to check his condition. I wondered if he ended up like this because I messed up. If he was in this situation because of my failure. Then I couldn't forgive myself.

Yes, I was a failure. That might be why my father and mother abandoned me. It was also because of that my sister didn't come looking for me.

It is also because of it that my brother hates me.

Right before I could step on the magic circle, he moved. His hands moved.

Thank god that he is alive. Wait, he is a Heroic Spirit so he should have long died.

But I wonder what Heroic Spirit he is.

Before that, I should make sure he is alright.

Next, I saw his eyelids twitch. He opened his eyes. They were beautiful. He had a beautiful pair of red eyes. They shined like gems.

I was going to call out to him when I made eye contact with him. It was for a brief moment but I saw it.

My body froze from fear.

I couldn't get the words out of my mouth.

In his eyes, I saw many worms squirming around. The worms had been patched up together to create a single entity. It also had tentacles with many eyes on it, the tentacles were squirming around. Each worm had a big eye and there was some sign made on every pupil of all the eyes.

It was a Giant Monster made up of worms in the shape of a human. Even those tentacles were made of worms.

As I looked at them, I couldn't move. It was as if time had been frozen. In the brief moment I had laid my eyes on the monster, all the eyes on the monster turned towards me. They were all staring at me.

I couldn't move my body.

In those eyes, I saw that weird sign or symbol. I wasn't sure what it was.

It was far more horrifying than what I have been through. The worm chamber of Grandfather couldn't compare to it.

I couldn't get my eyes off it. My body refused to move. It was as if my body had been hypnotized. It refused to listen to me.

We kept staring at each other. Right when I thought that I had seen it all, in those eyes, I could see A Giant City.

In the city were many buildings. Each is unique from the other. But I couldn't see any occupants of the city.

It was an abandoned city.

The walls and buildings were made with ancient architecture. Made from unknown material.

They had many unknown inscriptions on them. Written in some long-forgotten or some alien language.

It was a Giant City cloaked by dark clouds with occasional lightning streaking past the clouds.

In the centre of it was a Giant Building on an elevated platform. Maybe it was a pyramid but I wasn't sure of it.

I was seeing visages, I was being forced to see them. It was as if there was this will that was forcing my body. I couldn't move my body nor could I take my eyes off it.

I was being forced to watch.

From the moment we made eye contact it was as if I was but a puppet and he was the Marionette.

It was a silent city.

There I saw it in the Giant Building at the centre. It might have been a temple I am not too sure.

It had these engravings with some taboo language or foreign language, alien to mankind.

That's the feeling I got from it.

Its architecture told stories of the old days maybe older than our world.

The temple was a spacious one, supported by giant Pillars. In the grand hall, everything was frozen. As if the concept of time didn't exist in this ancient temple, an abode of an Ancient God.

In there suspended a being rest. At first, I couldn't see it but now I could see it. A being of Vantablack Body with a Purplish Violet hue covering his body and highlighting various parts of his body. Outlining his body to announce his existence to the World.

Without it, he would fade out of existence from this reality. Light bends near him.

His body was suspended in the air upside down.

I kept staring at him but there was nothing I could do. It happened suddenly but the being locked eyes with me. It was sudden but I could feel blood oozing out of my eye. I was crying blood, I felt my brain being squeezed. I felt breathless.

They were vast, black voids that seemed to absorb all light around them. For a fleeting second, I glimpsed galaxies swirling within those pupils, stars being born and dying in a cosmic dance that defied all reason. At that moment, I knew I had not summoned a mere man but an entity far beyond my understanding a being of ancient terror.

As I gazed into those abyssal eyes, I felt a primal fear grip my heart. It wasn't just his eyes that unsettled me, his entire presence exuded a wrongness, a discordance with the laws of nature and sanity. The air around us grew heavy with an oppressive silence, broken only by the faint sound of my ragged breaths.

My view changed, I who was inside the temple was now outside it. Just a moment before the town was empty. But now the temple was surrounded by beings made of darkness. Ugly monsters and beings of different species surrounded the temple. They were all different yet there was one thing they all had in common. They were wearing a black hood.

The skies above these nightmarish realms were a sickly hue of green, streaked with lightning that danced like the tendrils of a malevolent serpent.

They were chanting some prayer in an unknown language. I couldn't hear them.

The chanting continued. Yet I couldn't hear them.

Blood oozed from them yet they continued.

Through the pain, I struggled to comprehend the chanting that echoed around us a chorus of voices in languages both unknown. Each syllable was a discordant note in a blasphemous symphony that heralded the arrival of an entity beyond mortal comprehension. Their chant affected reality, and the world responded to it but I still couldn't hear them.

I got curious about the things they were chanting. Their mouths moved but no sound came of it or it might be that I can't hear them.

The blood stopped, and my eyes stopped dripping blood.

But the pain in my head didn't stop. The pounding increased.

I felt the pain. It was as if someone was squeezing my brain.

Despite the pain, I was curious about their chant. I tried listening in, but it was only a word that I heard.

§×¶¥¢®€~¿^¥©

I couldn't understand what it meant. Neither could I make note of it.

But as soon as I heard it, my brain screamed in pain. It was unlike anything I had felt before.

It was as if the chant was tearing apart my very existence.

The pain was unreal. Even in this crisis I can't help but think of Senpai, Sensei, Father, Mother and Sister. All those precious people in my life.

Am I going to die?

As I felt reality fade away I heard a cough.

The sound of a cough brought me back to reality. I looked around to see that I was still back in the underground chamber. Nothing had changed. It was the same as before.

Grandfather still stood where he was and hadn't moved an inch. Brother was still looking at the Man. As for the person in question, he was still sitting cross-legged on the floor without a care in the World.

It was as if everything I saw was all but a dream.

I checked my face and the area under my eyes and there was no blood to be seen. Yet I felt a pain in my head, declaring everything I had seen till now as real and was not a dream.

Nothing had changed in reality, as time had been frozen all this time. I blinked, and yet it was the same. I couldn't fathom what I saw. I was a having hard time processing it.

The pain still did not go away.

All this time I had been looking at him frozen. I was afraid to look at him now. My body quivered looking at him. Despite all that has happened all he had to say was.

"Were you daydreaming?"

Just what are you?

-----------------------------------------------------------

**The End**

Drop a comment and leave a review. Be it negative or positive but make sure to give constructive criticism. Also if you think you can add anything of value to the fic, then you are more than welcome to comment. Any thoughts or questions, ask them in the comment section. I'll try to answer them as soon as I can.