Authors's Note: Hey there! This is my first attempt at writing a story based on the Fate franchise, so I decided to act on this little idea I got a long time ago. Constructive criticism is welcome! Big thanks toHopeyMcHope for beta reading and suggestions.

Chapter 1

Kariya Matou stood in front of a large, ornate circle with a pendant in the middle.

"Oh, so you bring this back in lieu of a proper catalyst? My, my, Kariya. You truly are a failure."

Zouken's tone could have frozen the entire world as he regarded his grandson with scorn and derision.

"Are you sure you don't want to use my catalyst? You know that it would summon a better Servant."

"Shut up," Kariya spat. "I don't want any help from you. Besides, I did my homework. The Avenger class is best suited to my needs."

Kariya had spent his year preparing for the Grail War and trying to decide which Servant to summon. The main problem would be the worms. He could supply any of the Servants with prana for a short time, but he would certainly die quickly. In fact, he would definitely die before winning the Grail if he tried to summon any of the standard Servants.

However, when researching past Wars, he found a footnote regarding the Avenger-class Servant. The books simply offhandedly noted that an eighth, weak Servant had been summoned in the Third War by the Einzberns, and it had died quickly. Kariya was intrigued. Even his grandfather never spoke of this class. Was it possible that he did not know of its existence?

Kariya needed to know more. He had snuck into Tokiomi's mansion a few nights ago, trying to find more information on the Avenger class, when he came across a book dedicated to all the Servant classes. The book was dusty and seemed about as old as Zouken, but Kariya managed to obtain the information he needed there.

While the Avenger-class Servant tended to be weaker than the other seven, Kariya found his lifeline in its Prana Self-Replenishment Class Skill. He decided that he could simply give Avenger orders while he himself rested safely out of the sight of the other Masters. Of course, part of it was that he was rather enamored with the idea of summoning an incarnation of vengeance.

After all, he had plenty of grudges.

Unfortunately, he had only managed to steal a gem from Tokiomi's mansion as a catalyst. It would have to do.

He grit his teeth. The newly implanted worms were still something he was getting used to. They squirmed inside of him, crawling through his flesh as they searched for his Od to devour.

Sakura...is this what you have had to endure?

Kariya clenched his fists. What he wouldn't give to tear the old man next to him apart.

"What? Are you just going to stand there, Kariya?"

Zouken smirked as he mocked his grandson. To think that Kariya would come back now, after having fled the family so long ago. All to save a little girl that was handed to Zouken like some secondhand clothing. He chuckled at the thought. Oh, how stupid his grandson was. How suicidally stupid.

"Shut up, you son of a bitch. I'm doing this for Sakura, and Sakura alone."

"Oh? So your desire to trump Tokiomi has nothing to do with it?"

Kariya went rigid as he processed what Zouken had said.

"Oh, I see. Do you still think you can win back Aoi? That she is an unwilling participant in a cold and loveless marriage? She did bare a child for him, Kariya. Perhaps there is more to it than you think."

Zouken grinned. Oh yes, he would enjoy this. Both the worms and this were part of his punishment for fleeing. If this useless piece of trash won the Grail for him, so much the better. He would even give him Sakura. But Zouken had decided that the worms and Kariya's participation in the War was enough for him. Anything else would be an added bonus.

By this point, Kariya was shaking. There was no way Aoi still loved Tokiomi. After all, he saw her crying as Tokiomi gave Sakura to this monster. How could she still love him after that?

He breathed in harshly. He couldn't afford to be distracted right now. He had to focus on getting into the war and summoning his Servant.

"I'm going to start now."

He fixed his gaze on the circle and held out his right hand.

Fill, fill, fill, fill, fill.

Repeat five times.

But when each it filled, destroy it.

Heed my words.

My will creates thy body, and thy blades creates my destiny.

If thou heedest the Grail's call, and obey my will and reason,

Then answer my summoning!

Let all those who witness thee tremble in terror and dread,

As thou wreaks thy terrible justice upon the guilty!

A blinding burst of light erupted from the circle, overwhelming the room in a torrent of brightness as the ritual completed itself. When the two men could see again, they saw another man now standing in the circle.

He was dressed in a blue overcoat with black armor underneath. The Nordic runes on his armor glowed in the dark room, giving him a sense of age and power. He was tall, towering over both Kariya and Zouken. The contrast between this red-haired man and Zouken's decrepit form would have made Kariya snort had it not been for the gravity of the situation.

However, his amber eyes, as they gazed into Kariya's own, struck him as the most memorable. These were the eyes of a man who had seen horror and death, and Kariya knew that those eyes could harden at a moment's notice if the man wished them to. Yet this man chose to keep his eyes soft and gentle, as if to invite all who beheld him to be his comrade.

The man looked around quizzically. He had clearly not expected to be here. Then his eyes darted to Zouken and after that, Kariya's Command Seals.

For a split second, shock and surprise were written on the man's face, before morphing into grim determination.

Smirking to himself, as if enjoying an inside joke, the man spoke:

"I ask of you…"

The man looked straight at Kariya as he asked his question.

"Are you my master?"