Collapse of Dimension 2: World of Fate

Fate: New World

David:
- WOOOAH!

David falls and hits the ground

David:
- WHAT WAS THAT?! Portal appeared out of nowhere and just sucked me in.

David looks around and notices he is in the church.

David:
- This place... Looks like Church. Why did this place summon me? Am I going to fight the Devil or some shit?

A Priest appears and noticed David and says:
- Young boy, what are you doing here and why are you destroying the holy benches?

David didn't notice that he landed on benches and destroyed them.

???:
- This is disrespectful. For entering thy church and destroying what does not belong to thou, thou shall be punished.

David:
- Huh? Who said that?

Blue flames appeared behind David, flames disappears and man appears in their place. He is about to slash him with his sword in order to behead him.

Priest:
- Assassin, wait.

???:
- Why do thou order me to wait, Master? He hath disrespected a God of thous.

Priest:
- Let him explain yourself first, it might have been just a coincidence and we accused him for something he didn't do.

David:
- Um... Thanks.

Priest:
- Young boy, please explain what are you doing here?

David:
- H-how I could know? I just got teleported here out of nowhere and landed on this benches. I didn't really destroy them on purpose!

Assassin grabs his sword. Priest stops him.

Priest:
- What do you mean by teleportation? It's impossible for humans to teleport freely around the world.

David:
- I... Usually... Well, that's complicated. I usually create portals to travel through dimensions but this time I guess I was summoned by somethin-

Assassin attacks David but he blocks it by catching his sword.

David:
- Woah, hold up, big guy!

Assassin:
- He is a servant, Master. His Master should be around somewhere. Don't let thour guard down.

David:
- Servant? I don't serve anyone, I don't know what you're talking about!

Priest shows a sign to Assassin to make him stop fighting.

Priest:
- Wait before killing him until I say so, Assassin.

Assassin:
- As thou wish.

David:
- Woah, for a Priest you aren't really a Priest like...

Priest:
- I'm assuming you are the Servant summoned by not someone but something. There is no magical circle anywhere. I was in this room a few moments ago. There is no way any Master could complete a ritual so quickly. He might be the Ruler, someone who do not participate in Holy Grail War and was summoned by Holy Grail to investigate something rather abnormal. Am I right, Ruler?

David:
- Ruler? Me? You seriously got the wrong idea... Holy Grail? What is even is that? But you've mentioned something about war so I assume it's rather important item.

Assassin:
- He must be bluffing, Master. A servant who knows nothing about Holy Grail nor war should never been summoned here or at least he should have gained the knowledge about Holy Grail and war, especially Ruler class.

Priest:
- Perhaps, you've hitted your head and lost your memories?

David:
- Umm... I definitely didn't lose any of my memories but "assuming" I actually am a servant and was summoned by someone or something, could you explain what Holy Grail and war over that thing is?