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: 3550 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.

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General POV

Fuuyuki City, Japan

"Were you daydreaming?"

"No"

Sakura not wishing to anger or upset the ancient horror that sat in the form of a man in front of her spoke. She wasn't used to such situations but growing up with a complicated family, a jealous brother and a crazy ancient magus masquerading as a family member looking after his descendants albeit discretely trying to fulfil his wish of gaining Immortality and trying to train his adopted daughter aka Sakura with worms had at least trained her enough to maintain her cool despite the inner turmoil.

Though her cool broke with the matters involving love.

Lord of the Mysteries had hijacked the summoning circle to participate in the Holy Grail War. Despite coming here unintended, the matter of his participation was yet undecided. He hadn't decided whether he was going to participate in the War or not.

"So who are you?"

"I'm Sakura" the girl introduced flustered, when Lord of the Mysteries turned towards the boy. The boy maintained his silence. Sakura did not wish to anger the being answered on his behalf.

"He is my brother, Shinji, Shinji Matou. The person standing behind me is.."

As Sakura was going to introduce Zouken, Zouken curious about the Servant chose to hijack the conversation.

"I'm Zouken Matou. Now, who might you be?" Zouken stepped forward as he spoke. Just before completing his sentence, he knocked on the floor with his cane.

Lord of the Mysteries surprised to find the names of individuals got up. He picked up his cane while he was at it.

'So, she is Sakura Matou or formerly Sakura Tohsaka. Her brother Shinji Matou the predator and there's Zouken Matou the Old Bones. So, it's fate verse that I have found myself in. Seeing that she is in her mid-teens, this should be the Fifth Holy Grail War. World? '

Despite asking a question, Zouken stood in his position trying to Guage the Servant that Sakura had summoned. He was shocked, to say the least. She had failed the summoning yet there stood a being.

Due to the failure, she had failed to use the catalyst he had procured. It was an artefact from Greek Mythology, more precisely he wished to have her summon Medusa with this.

What's done is done. There was nothing he could do now. They couldn't cancel the summoning. All that was left was to see if he was any stronger or was the summoning truly a failure.

After his introduction, he was still waiting for the man to respond. Whereas Lord of the Mysteries was trying to contact the World only for it to fail. Despite his many attempts, everything failed.

Seeing that he was getting nowhere, he turned towards Zouken to get this stuff out of the way. He could try contacting World later.

"So, it's Zouken Matou, Shinji Matou and Sakura Matou. And it was Sakura Matou who summoned me."

"Yes", Sakura answered Bruce as he turned towards Zouken.

Zouken was still waiting for his answer. Though Bruce had tried and thought of a lot of things in the meantime not a lot of time had passed in the Real World. It might have been his Stats influencing him.

Sakura was scared to move from her position but she had steel herself. Grandfather had asked him a question and HE had yet to answer them. She dreaded the outcome where Grandfather or Shinji battled HIM. Not wishing to prolong it any longer, she risked it.

"Excuse me. I was wondering what should I address you as?"

Hearing the question, Bruce wondered. He moved and surveyed the place as he owned the place. He was not worried about anything. The strongest being in the room except him would be Zouken. If it was just him with Yggdrasil's prowess he might have been careful. But he had Gilgamesh and Gojo Template. Especially Gilgamesh Template was enough to take care of most beings in Fate verse.

Added with his Yggdrasil World Enemy, World Champion and Gojo Template. He could act freely in this world except for when he faced Beast Class Monsters. With his prowess, there were very few people he had to be mindful of. Still, it did not give him the luxury of error. Though he was strong enough to defeat them, there was still an army of beings in this verse capable of harming him and maybe even killing him. All it took was a single mistake from his side and he could end up dead.

"Hmm! My name is that what you wish to know?"

"Yes," Sakura nodded repeatedly as she answered him.

Lord of the Mysteries looked at Zouken, 'Shrewd Old Man' when his gaze moved to Shinji. Bruce did not have much of an opinion of the boy except that he was better than Dead. Lastly, he looked at Sakura as he answered her.

"Name huh! I have been called by a lot of different names. I have a lot of names but you can address me as.."

He thought of it, what he would like to be called as.

"The Fool"

"The Fool"

Sakura repeated after him. She again looked at the Magic Circle where the card had fallen off. It was right there but now the card was nowhere to be found. It might have been burned after the surge of mana at the end of the summoning.

"The Fool. What sort of name is that? Tell us your real name. As a Heroic Spirit, you should have a name right? To have left a mark in history to be labelled as Heroic Spirit."

Shinji was an impulsive Man. He was always careful of what he did. Always treading along the safe path. Yet he misspoke this time.

It might have been because of what happened at school but he was not in a good mood today. It was the Death Card, continued by Sakura's successful summoning and Shirou's pesky behaviour at the club. All he could think of was how to remove him from the club. All of it was piling up for him to take it all out on the Servant.

He also had insurance in the form of his grandfather here to stop if things go south.

"A Heroic Spirit you say. I am not sure of it, boy."

Bruce knocked his cane on the floor and moved his hat while he spoke. 'I've decided on the path I will take in this story. But I've yet to figure out which path this is. Whether it's the Saber route, Rin or Sakura route. Then I can plan accordingly.'

Shinji was dumbfounded by the answer. The same was true for Sakura.

Whereas Zouken was taken aback by the answer. He first wondered who this 'The Fool' could be. As he heard the answer he observed it now. The answer had been in plain sight all along. The being that Sakura had summoned was not a Heroic Spirit. To be a Heroic Spirit, the being had to first die. But the being who stood in front of him was very much alive.

She had summoned a living entity for the war.

'How is this possible? It was wrong on a lot of fronts. If he was still alive then what was their relation now? Would Command Seals work on him? As the founding member of the Holy Grail War, he tried checking the status of the War and the being in front of him. The man was definitely participating in the war. He had after all taken up a spot among the Seven.'

"I'm not a Heroic Spirit. I'm very much alive. Also, neither am I a servant."

Sakura heard him talk, her heart skipped a beat. He was alive. She cursed herself for the failure. She looked at the Command Spells and him.

Zouken moved behind Sakura and used his crest worm on her to use the command spell to bind the Mysterious Man.

"The summoning wasn't a failure."

Zouken could now see it, it wasn't that Sakura had failed to summon a Servant. The Demon that now stood in front of them had trespassed upon their summoning.

The crest worm did its job. Yet nothing happened. When Zouken moved to check the command seals on Sakura's Hand and the crest worm. The seal had failed to activate.

"Grandfather?"

Shinji afraid of the action turned towards Zouken for answers. Zouken afraid of the outcome tried using his worms to buy him time to escape.

{Flaming Blaze}

A lower version of Primal Blaze where the spell incinerates everything with the pillar of flames within the range of three meters of the caster.

All the worms left on by Zouken were burned down by the spell.

Sadly Bruce couldn't allow it. Zouken Matou was a formidable adversary. He was the one who came up with the Command Spells.

He was unsure of why he moved to confront Bruce.

He couldn't allow Zouken to escape after attacking him. He was lucky that the command spell didn't work on him. Though he did not know the reason he was happy with the outcome. It was because of this that he couldn't allow him to escape. Now that he had come in as a Servant. He couldn't allow Zouken free.

Who could say if this world was the same as anime? Here Zouken could be all-powerful. Though not as strong as to defeat him but still has the power to create a superior version of his previous creation, Command Spells.

One that would work on him.

To not let him escape, Bruce counterattacked.

Zouken was on the verge of teleporting when he was faced with,

{Reality Slash}

His body was severed in two halves. The worms moved to combine but they failed. The worms that suffered the cut refused to respond or join. Though the rest of them were fine except for some injuries.

To pile up the damage, Bruce continued.

{True Death}

The worms struggling on the floor died.

Lord of the Mysteries walked towards the worms as he inspected them to make sure the Man was dead. In the end, He was not sure though.

---

[True Death]

Zouken was a persistent man. His worms were his cover. He used them to camouflage his truth. As long as his true body was unharmed, it didn't matter. No damage inflicted upon the worms would matter.

Similarly, now he had woken up in his true body. His body was stored in an underground room of an old manor that belonged to him.

It was a hideout that he bought for safekeeping. He would have never imagined his worms to be killed too easily. Never had he faced such situations. Usually, he would buy time with his worms for him to escape.

Despite the security, he roamed around in his fake body. His real body was very weak. This was also one of the reasons why he was getting desperate to get the Holy Grail.

As long as his real body lived, he would live. He chuckled as he thought of the Man that Sakura had summoned. He might have to finally give up on living with his family. At the very least until the end of the Holy Grail War.

He suddenly grew curious about the man that was summoned. He was curious about the identity of the caster or whatever class that man belonged to. To so efficiently take him out, within seconds since the Battle started is an achievement.

Zouken wasn't sure if even Kischur Zelretch Schweinorg could take him out with such efficiency. Growing curious of the Man. He checked his worms, lucky to find a few still alive.

He possessed it to get more information about him. But sadly the Man noticed him. He thought of giving up the control but his curiosity got the better of him. He waited to find the method The One called Fool might use to kill the bug.

To only decide the result wasn't worth the risk. He called off the connection and moved outside to empty the place. He couldn't let the Fool know of his location. Just his possessing the worm might have clued him off his survival.

His techniques, spells and skills were still an unknown aspect to Zouken. He first had to collect more information to best respond to him.

"The spells that he used are intriguing. I a haven't seen anything of their kind."

Zouken sadly had locked his fate the moment he had decided to check up on his worms.

As Lord of the Mysteries stood among the pile of dead worms looking at the result of his action. He dreaded the result had he not faced Joker.

He would have not had the courage to face Zouken now or the determination and the strength to kill him.

'I would have hesitated. Or be scared to make a move.'

He stood there unmoving as he looked at Shinji and Sakura. Shinji was screaming his mind out. He fell on his back in fear. Looking at the carnage, he was too afraid to talk. As Shinji locked eyes with The Fool, he was too scared to be in the same room.

Shinji somehow managed to gather enough strength to move his body. He got up and ran abandoning Sakura in the process.

Zouken had made it just in time to watch the whole spectacle. He not wanting to risk it got rid of his link. Though he got rid of it, the worm had been connected to his soul till now when Zouken rid himself of the link.

Lord of the Mysteries observed a worm squirming at his feet. He stood there as he watched Shinji run away from the underground chamber. Yet Sakura remained routed to her place. She was too afraid to move.

'I'm having a headache thinking of the future now. Maybe I shouldn't have killed him. But whatever, he had to die. It was now between him and me. Only one of us could live. Just like this worm.'

As he finished his monologue, Bruce squashed the worm that was alive with his cane.

---

The Root aka Akasha

Lord of the Mysteries or the Fool was quite different from other players of Yggdrasil who transmigrated.

They transmigrated with their Yggdrasil Character and items.

Each of them with its unique flavour text.

Normally it's the Overlord World or the New World that transmigrated the players. Dragon Emperor's magic that brought them to the New World.

It was that magic that brought a few lines of code to reality.

It wasn't just that, it also brought the flavour text of those items to reality. But unlike his Guild or the other players, Bruce never made it to the New World.

Neither did the Dragon Emperor's Magic affect him like others.

It was ROB who sent him to another world. It was Fate or Nasuverse. Due to the ROB factor, Bruce was able to bypass into the Nasuverse from Overlord Verse.

Normally it would have been impossible. Overlord Verse is quite weak compared to the Nasuverse.

Despite heavy flavour text to the spells, it might be boosted to an unimaginable level. Yet it can never overcome the limitations of the Universe.

Despite its great strength compared to Nasuverse, it would still fail. Even World Items would still end up as A-ranked Noble Phantasms. Shying away from being the strongest of items. All because of its origin being from a lower-ranked or less powerful verse.

Yet for Bruce it is different. He made it into Fate Verse through Heaven's Feel System, hijacking into Throne of Heroes and by extension The Root or Akasha to bring his identity to reality.

The power difference between The Root and Dragon Emperor is quite vast.

Which makes his every move more Impactful to their lore. His spells held true to their lore.

Even the spectacle Sakura witnessed by making eye contact with him was due to his Character Lore.

His lore as the World Enemy aka Cthulhu or The Fool dictated he has Causality Manipulation with Reality Wrapping or Outcome Manipulation aka Wish.

It might have been his wish, as unlike the game he was not limited by the system. Where he could only use wish after losing 80% of his HP.

It could have been his Wish or his suit that protected him from the Command Spell of Zouken. Only ROB knows the answer to it.

Unluckily Zouken had made an enemy out of someone he never should have. At the same time, The Fool squashed the worm with his cane, and Zouken's soul was wiped out of existence.

It could have been the cane or the wish but Zouken was no more. Even the Root was left helpless in this situation. Neither could The Fool himself bring Zouken back if he so wished.

---

Zouken's body fell on the floor. There was no struggle, it was a swift end. An anticlimactic end for him.

Whether he deserved it or not was questionable.

His body lay on the ground as his hands pointed towards the sky. Though he did not get a chance to question his reality, his expressions spoke volumes.

His hands trying to clutch the Akasha begging for justice and yet there wasn't anyone there to answer him.

Zouken originally wished to create a world of good and eliminate all evil from the face of the earth. He was the patriarch of the family back in the day. He had ties with Tohsaka, Einzbern and even the Apostle of the dead, Kischur Zelretch Schweinorg.

With a strong background and as a strong mage he was also in line to inherit the Jeweled Sword of Zelretch. If not for Kischur Zelretch Schweinorg pronouncing them as an evil family.

Yet it did not deter him. He pursued his dream until he was devastated to find that it was impossible to achieve his dream in this World. At least not in his human body. Which lead him to pursue Immortality.

He was then friends with Nagato Tohsaka and Justeaze Lizrich von Einzbern.

Together they brought about the Holy Grail War. Nagato Tohsaka offered the Fuyuki City for the Holy Grail War where as Zouken Matou worked on the Command Seals for the Master to command the Servant throughout the Holy Grail War.

Justeaze Lizrich von Einzbern developed the Heaven's Feel System and also offered Homunculi to act as the vessel for the Holy Grail.

He was obsessed with the Holy Grail for his Immortality.

Justeaze Lizrich von Einzbern also sacrificed herself to act as the host of the Grail. Zouken was devastated by it, he had liked her back in the day and it saddened him to find her sacrifice.

Though he steeled himself to watch the Holy Grail to the end to honour her sacrifice.

Through the ages he lived, he got lost in his goal. Only seeking Immortality now. In search of Immortality, he was ready to sacrifice anything and everything.

He had lost himself to the goal along the way. He remained as an empty shell of what he once was.

As for Sakura, when Zouken got to know of the decision of Tokiomi Tohsaka to only train Rin the eldest daughter of the magecraft, he had offered to adopt Sakura into his family.

The Mage family each have a secret art of their own. As a tradition, they pass it on to the next heir of their family. To continue the family line and strengthen their family. To also not cause in-fighting for outsiders to take advantage of, they limit it to only one child. They train and pass on their collected wisdom and knowledge only to the eldest child of their family.

Though he had adopted her, his intentions were unknown at the time and his reasons still questionable. He hadn't done a very good job. It was apparent through his actions, he had been too fixated on his goal to achieve Immortality.

Zouken's life had been a roller-coaster so far. It hadn't been a long time since Bruce entered this world and he had already changed a lot of things.

Zouken was erased from the annals of the multiverse of the Nasuverse.

It wasn't just the Zouken from the Stay Night verse that died but every Zouken met their demise at the hands of THE Fool.

Zouken from every route of the Fate series.

Changes at the universal level were happening by his simple action of using the cane to kill a person.

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**The End**

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