Kariya Matou’s Amalgam System

After almost murdering Aoi Tohsaka, Sakura's and Rin's mother, while also driving her insane in a fit of madness, the mental state of Kariya Matou started to decline as he headed towards where the one little girl he needed to save was located.

With Zouken having left to pick up what was left of the corrupted Holy Grail to create a second Lesser Grail with Sakura's body, this was the perfect chance for the man to save his adopted niece...!

The broken figure of what was once an ordinary reporter squirmed as the battle taking place between his Servant, Berserker Lancelot, and Saber Artoria killed him slowly, draining what was left of his magical reserves as the Heroic Spirit contracted by him ate away at him without caring for his wellbeing. It would to the point that he started to see hallucinations of that little girl...

He started to hear Sakura's voice asking him:

"Why are you suffering so?" Her tone was innocent as if unable to fathom his current situation.

"Because Berserker has... to fight..." He vaguely remembered the man who had given him a deal he couldn't reject even if he wanted to. The devilish figure who approached him in his darkest hour.

"Why?" The girl asked in an innocent yet tired voice as she could see no point in his struggles.

He knew all to well even while being tricked by his eyes. No one could escape from Zouken's grasp...

"Because the priest said so." Even he started to notice a contradiction in his mind as he spoke.

"The priest?"

"Yeah, he promised to me... That he'd give me the Holy Grail. If I have the Grail, I can rescue you." Not even a little girl in his imagination would be fooled by this proposition... that was too good to be true.

"You're going to save me?"

"Yeah... Remember, I promised... that we'd all play together, like we used to..." He remembered back to the days everyone was happy. Even Tokiomi had a part of him that loved his family despite being an old-fashioned Magus who was tied by traditions.

"Then, I can see Mommy again?"

"Your mom...!" His quickly eyes dilated as he was unable to bring himself to speak of his greatest sin. In his blind fury, he had taken the mother of this pitiful child with his own hands. The image of Aoi looking down on him like she did when he was framed for Tokiomi's murder appeared as an illusion before his eyes, overlapping her small body.

The illusions broke after a sharp sensation could be felt once Lancelot started to go all out.

His nails grasped into the ground as he started to scream in extreme pain. The feeling of his life force being sucked out of his Magic Circuits was unbearable...! Not even hitting his head into the wall behind him could offset the immense pain.

Berserker wasted away his magical energy, all for the sake of killing the woman he hated so dearly.

It was the moment the wraith of a once celebrated knight finally have his heart stabbed through did he finally feel free from the constant drain of magical energy. However, it was already too late by the time it had happened... as all his Crest Worms depleted.

His Blade Wing Crest Worms all died, cutting off his deeper connection to Zouken in the process.

The old ancestor knew that he was doomed...

His body slumped to the ground once his suffering was finally over. He wanted to rest, but the will that had driven him this far wouldn't let him. This was the man who endured much worse pain throughout the war. Even if the woman he loved was no longer driving him, Sakura was still someone who needed saving from the vile family that was his own...!

He lifted his body up and continued to go where the little damsel in distress was being held captive against her will. He may not be the most purest of white knights, but his only desire left was to save at least that one girl who deserved a happy ending.

Kariya limped, holding his arm as he finally saw a figure wearing a familiar purple dress in a hallway.

"Hey, Sakura-chan..." He called out to her, unable to even muster up the strength to reach his hands.

"Uncle?" The young girl was surprised as he came back looking like he was edging towards death...

The last of his life force was wavering... He was like a candle flickering in the wind in his last moments.

"I'm here to save you." He repeated the same words he had been thinking in his head as he was coming to this place. The dream he was unable to let go of caused him to ignore his own condition.

"It's okay now." He continued, unable to register the horror in her darkened eyes which were seeing his situation differently. A part of her want to believe in him, yet a dark corner of her mind didn't dare to have hope even if 'rescue' seemed close.

She watched the man who was closer than her actual father grabbed her arm and tried to bring her away from the bug pit she had to consciously torture herself in every night. She could feel the incompatible Spells of the Matou Family being engraved into her with every time she did this even if she knew nothing when it came to Magecraft.

"Let's go." His words brought her back to reality as she could only watch in sorrow when those weak arms started tugging at her. Sakura could feel that even her tiny arms were strong enough to push him away, but chose not to in respect for her Uncle.

She thought he would bring her away, but his hand started to become colder as he spoke a name:

"Aoi-san." These were the last words he spoke before the last bit of his strength faded from him.

She was unable to react as he fell on the stairs to the worm pit, his eyes no longer containing life. It was a scene that brought great anguish that her tortured self was unable to even express properly.

"Fool... That's what happens when you disobey Grandfather." There was a repressed anger in her eyes not from knowing he failed to save her, but the fact that he gave his life to try and fight against the terrible monster who was her demonic captor.

She couldn't even shed any tears as she felt it would have been better for him if he had stayed away from her. Sakura hated Kariya Matou, but she hated the girl he sacrificed himself for so much more to the point she couldn't accept reality.

The girl was unable to handle the scene as her thoughts started to rationalise his lifeless corpse:

'Uncle Kariya... Is he dead now?' Was what she thought on repeat in her madness before moving onto her next thought: 'I don't understand... Why did he come back here?' It made no sense for someone who could've escaped to come back.

His love was the farthest thing from her mind...

'Why...' She watched his body slowly lowered into the worm pit, unable to move her body as her expression was stiffened badly: '...did he want to keep living, even in such a state?' She looked at his white hair and right eye that had become blurry.

'Why...' Those hands that once her own warmly like she was his own daughter were the last parts of his body she could see as he was being devoured by the magical insects: '...did he have to die such a meaningless death?' Her own thoughts pained her.

It was at that moment she had a eureka moment in the depths of despair as she came to a conclusion:

'Oh, I see...!" She thought of the demonic old man who was the reason she suffered: 'This was a lesson for me. Anyone who resists him or step out line will end up like this... Grandfather must have let him live... in order to teach me that... Yes, I understand now... Grandfather...' She became a living corpse as her body did as it had always done.

Even without her consciously thinking, she started to walk towards the bug pit of her own accord. A dark part of her mind was unable to let go of Kariya as she stepped off from where he had fell. Again, a great amount of pain went throughout her body just like always as she descended into the abyss. It was only the coldness of Kariya's corpse that allowed her to stay sane as the worst tortured her.

Meanwhile, a tiny glimpse of magical energy that was insignificant enough to ignore appeared in the broken man's eyes as his consciousness was transported. He was strangely at peace as he saw the spirit of his armoured Servant in a white space.

The black armour vanished, revealing the face of the knight who had regained his sanity. The purple-haired man looked at him apologetically, and bit his lip when the makeshift Magus spoken first:

"So we're both dead?"

"...Yes." Lancelot nodded with a complex look. His response caused the white-haired man to sigh:

"So you're returning to the Throne of Heroes?"

"I chose not to." These words confused the man who had already lived to the end of his tragedy.

"Then what are you doing here?"

"Returning the favour for what I'd done." The knight started to turn into rays of light that were entering Kariya's body. A strange screen appeared before him along with words he didn't understand:

[Conditions met... The consciousness of a Heroic Spirit is being sacrificed to appeal to the Amalgam System... Accepted! Synchronising with the current Host... Success! Emergency measures are being taken... Authorisation used to independently act...]

[Initial 'Amalgam Tokens' have been sacrificed to open up the 'Bleach Branch' of supernatural abilities... Applying 'Plus spirituality' to the Host's soul... Currently fusion with Magic Circuits...]

A bunch of notifications made the white-haired man shocked as he couldn't understand what Lancelot was doing. The only thing he could even fathom was that he had sacrificed his 'existence'.

"...Why?"

"I don't want to return to the Throne of Heroes to be taken advantage of anymore. Use my power however you wish to save that girl, I hope one day you will achieve the salvation I will never attain." He gave a gentle smile as he vanished into thin air.

[Berserker Lancelot's Spirit Graph has been gifted to you... Factors are being considered for fusion...]

A bright light flashed, and he found himself back to where he had died atop of the staircase leading to the bug pit. He couldn't believe that he had been brought back to the world of the living, even if he was turned into an ghostly entity without a body.

He was unsure as to why there was a strange chain connected to the centre of his chest that seemed to be corroding with time. He could feel that his 40 Magic Circuits still existed even as a mere soul.

[The Host's Magic Circuits are bonding with the Chain of Fate... New possible transformations are now available... Saint Graph is now being adapted and amalgamated into the Host's spiritual body...]

Kariya couldn't pay attention to the notifications on the screen before him as he looked down to see Sakura lying in the middle of the worm pit while holding onto an arm that looked just like his own.

[Warning! Mental instability is causing the user's Chain of Fate to erode a hundred times faster...]

"Sakura!" He called out to her, but the young girl seemed listless as she held onto his corpse's hand.

She looked towards the ceiling with empty eyes...

It was at that point that the mental instability he was experiencing grew to the point that the Chain of Fate finally broke. The power of the Saint Graph he was gifted started to be corrupted in the process of him undergoing his 'Hollowfication'.

[Encroachment has reached its final phase... The Hidden Attribute of your Saint Graph is being altered... The System will be using its authority to retain the user's consciousness... Hidden Attribute has been changed to 'Beast'... Initiating evolution...]

The losing of one's Chain of Fate was like losing the ability to freely feel emotions. Once it was turned into a Hollow Mask, all that would be left is a being pure instinct. The System did its best to stop that from happening as he was becoming a Hollow.

Even as he was becoming a Demi-Hollow and insect-like appendages were growing out of his body, he used the Absorption Spell carved into his very soul to bind the Crest Worms to himself. This overpowered them as even his corpse became the target of the Matou Family's Magecraft which specialises in "to bind something to one's self".

Absorbing magical energy was only one facet to this Spell which added more variables to his great transformation. Even Sakura felt a change as the Crest Worms around her stopped carving the Matou's Magecraft efficiently into her mind.

Truthfully, she had already learnt enough from her previous experiences to know the concept of the Matou's Magecraft. The only reason she still dipped herself inside was out of fear for Zouken and nothing else. Her lack of pain perplexed her.

'Am I dying too?' That might be a better option than continuing to live under the Matou Family's roof.

[Due to the Host not being designated as a Servant or Demi-Servant, your qualifications as a Pseudo-Servant has been accepted... You have attained a total number of 10,000 Crest Worm vessels and your own human body to manifest as a Pseudo-Servant... Your new form shall take on aspects of both Beast and Hollow to create a new being...]

As this message popped up, Sakura felt something was off as her Uncle Kariya's body started to glow as the Crest Worms around her were being devoured into his corpse. She was unable to do anything but watch with tired eyes as she was lowered to the floor of the pit once all the bugs forming the torture room vanished into his body.

Just when she thought that this was a twisted joke from Zouken, the once lifeless corpse she continued to hold the hand of twitched. His blood started to circulate as warmth started to fill the one cold hand that she held onto since he died.

[The System is acting as a wall to block any and all mental interferences, and has separated all harmful components into Berserker Lancelot's Saint Graph... Designation of Lust has been born from your intense love and desire to care for another.]

Her white-haired uncle finally opened his eyes once again. This time, he no longer seemed as broken as he did before despite still having aged white hair. Both his eyes were functioning well as he saw her face, then hugged her tightly.

'Is this a dream?' If so, she didn't want to wake up whatsoever. She was fine with living in the delusion that her uncle had come back to life. Kariya spoke with excitement as the excitement from being resurrected flowed through his body momentarily:

"Let's leave this place." As he spoke this, his body tried to activate whatever power he could muster.

[For the sake of future mental stability, your Beast Hollow has been turned into Crest Worms... They have become Blade Wing Hollow Worms you can activate on command... Aspects of your Lust Designation is being added to your weapon...]

[Due to being part Hollow, you have failed to acquire your own 'Authority of the Beast' Skill...]

[Due to being part Hollow, you have failed to acquire the 'Independent Manifestation' Skill...]

[You are now a lesser Beast of Calamity, Beast III/S, of the Pseudo-Servant variety along with being a Vasto Lorde 'Highest Great Hollow'... Your Hollow Mask and Beast Crown have been fused and sealed along with your unique Class Skill...]

[Your Beast Hollow Class Skill 'Naga-Bloodlust' has been sealed due to risk of corrupting the mind...]

[Your signature Hollow Skill 'Bug Creation' has been sealed due to risk of damaging the body...]

[You are permitted to wield Arondight, the blade that has been touched by you Beast Hollow power.]

[You are permitted to gain an Possession Inheritance and Succeed Phantasm from Lancelot.]

Once he finally finished, he felt the strength of Lancelot flow into him as his bleached white hair started to take on a shade of purple similar to that of Sakura's. A sword appeared in his hand as his tracksuit was morphed into a futuristic skintight armour that was as thick as a finger's width. He felt as if Lancelot's Skills were being passed onto him much easier thanks to it being 'gifted' to him.

He could feel his Magic Circuits having become much wider as he felt immense strength flow through him. Sakura's eyes widened as she was unable to understand what happened to him.

She still allowed him to lift her into his arm before trying to leave the mansion, only to be stopped by a familiar figure who appeared above them. This was the same man who had watched Kariya suffer rather gleefully and schemed to 'use' Sakura.

"So you're still alive?" Zouken was intrigued as he saw the two purple haired figures from above.

He really wanted to take Kariya apart!