"This is the moment I had been waiting for ages! To the moment to blow the Gjallarhorn!!" Said the watchman of the apocalypse Heimdal from Nordic. "The time to open the curtain of Ragnarok is near!!! Are you all ready for this!"

A massive roar of excitement was heard coming from all angles of the audience sit, with each roar coming from many different phaetons of the Gods.

"The rules are simple! Fight to the death. That's it! The winner is decided by the complete annihilation of the other side."

"It's about to begin... Brunhild nee-san" said the youngest among the 13 Valkyrie sisters Geir nervously.

Brunhild on the other hand looked at the performance with a single sweatdrop.

"The first round! Introducing the vanguard from God's side this man! Everybody knows this God. Everybody wants to see his maximum power!! His Mjollnir can even tear apart the sea and lands! If he not going to fight then who else will? Live by fighting! Die by fighting! the Nordic strongest! The berserker of thunder!! The only the thunder god of Nordic Thor!!"

As a lone man with long red hair wielding a massive size hammer walked out of the gate slowly, again a massive amount of roar of excitement was heard coming from the Gods side.

"Crush and annihilate them," said the all-father of the Nordic God Odin.

"And! From the side of humanity! We have this person!" Heimdall shouted.

Smoke began to appear on the other side of the gates where humanity stand to watch, slowly a figure of a person began to walk out of the smoke the figure. 

There was a seen to be a man with short sharp blue hair with grey stripes, he wore glasses which add some more beauty to his face which end up attracting a few females of both the audience sit, the man was seen to be wearing a thick black suit that holds a few pieces of his iron armor, with two sharp iron spike and a blue cape attack on both his shoulder, on his hand that he holds a big yet beautiful sapphire like a sword with a unique body, and on his waist there it holds a few long daggers that hold the same property as his sword.

"And, now representing humanity for the first round, the posthumous child of 
Hjordis, and King Sigmund of Frakkland. He is known as one of the greatest heroes in northern Europe, the man who holds and reforges back the legendary demonic sword Gram to its former glory! Soon becoming a long-time military man of valor and then a dragonslayer by slaying the dragon Fafnir unabated. As he obtained the wisdom of the gods and power, by devouring the dragon's heart after beheading his foster-father Regin who tried to take Fafnir's hoard... The famous dragon slayer from the Volsunga saga! The King of warriors and the

"Wait! It can't be!" Brunhild shouted in realization.

"Yes, it is oldest Valkryie, it's none other than him, one you called your beloved that you've killed shall be the vanguard for humanity," Gilgamesh said with a slight chuckle.

"Wait for a second! That suppose to be your version of Brunhild nee-san former husband!?" Geir asked in shock.

"Correct you are, young Valkyrie," Gilgamesh said.

"He looks! Nothing alike at all!? With the nee-san version! I mean look at the giant sword, you're supposed to tell me that Gram was supposed to look like a giant crystal sword!?" Geir asked.

"Because he is from another timeline, his entire origin is different from yours as this version represents the true might of the king of a warrior," Gilgamesh declared to the Valkyrie.

"Especially after getting stabbed every day by his wife..." Gilgamesh thought, remembering back before they left he also got stabbed in the stomach by their version of Brunhild, he just hope that wound wouldn't be much of a hindrance to the vanguard performance.

"The king of the Volsunga! The mighty dragon slayer, Sigurd!!!"

The crowd soon answers Heimdall's final introduction with a loud and powerful roar of excitement, the two men standing in the arena were now facing each other face to face trying to analyze the capability of their enemy.

"By the looks of it, Crystalized Wisdom has been activated," Gilgamesh said.

"What's that?" Geir asked.

"One of his skills when he manifests himself as a heroic spirit, this skill allows him to gain every information of his enemy by its true strength to the hidden weakness that the enemy doesn't even know," Gilgamesh explained.

"That's... Pretty overpower," Geir said in admiration.

"Wonder if he also holds the same ability,"  Brunhild thought.

(The crowd's POV)

"So that's the king of warriors!" one of the men from the modern era said in wow.

"Wow! He is also an hoty," one of the modern-era teen girls said with a slight surge of lust in her heart.

"He looks like a nerd," one of the modern-era teen boys said.

"The guy looks strong," a woman from the Victorian era said.

"Wait, why does his suit look so advanced?" an archeologist said.

"Go, my son!" a scream coming from the top of the crowd sits, the scream alone manages to attract the attention of most humans on the stand.

There they can see a beautiful woman with long gray hair wearing a noble winter dress and a few golds accessory such as a necklace and a small crown on her head. This woman was none other than Hjordis, the mother of Sigurd, well to be more correct she is the mother of this world version of Sigurd.

"Kick their asses Sigurd!" Hjordis shouted before she turn her head beside to see an old man sitting calmly. "Come on dear, it's our son shouldn't you be cheering along he's fighting lord Thor right now!"

"I know," the old man beside her said.

"Then why aren't you cheering for him, it's a battle to decide the fate of mankind you know!?" Hjordis said.

The old man beside her only answers her with nothing but silence which got her nervous, but she just used that anger to cheer on her son even though she doesn't know that the one she was cheering on was just another version of her son, this old man was none other than Sigmund, the father of Sigurd and the former holder of Gram.

"I don't know how to tell her, but it best to keep her in dark as he can also die from fighting the lord Thor... I don't know who you truly are. But the one thing I know for sure is you aren't my son but can also be him at the same time either way I hope the best for whoever you truly are to win," Sigmund thought, he know how his son looks, and that is not how he looks like but either way he still hopes for him to win the first round.

(Back at the ground)

"So you are this world of Thor, from your body to that hammer of yours is none other than Mjolnir. I expect you to be much of a monster than the one I've met before, lord Thor," Sigurd said, flicking his glasses with his signature pose.

"I don't care what dirty trick you're going to use, you better be an exceptional opponent..." that was the last words Thor uttered, as he then fall behind his back and swung down his giant hammer toward Sigurd.

Answering the sudden attack Sigurd quickly in a flash brings out Gram in front of his face, as the sword soon collides with the hammer creating a small shock wave around the arena. After a few seconds of receiving the shock from the collision with the hammer, Sigurd then jumps back a few feet as his free left-hand grab one of the daggers on his waist he then threw the dagger as hard as he can toward Thor.

Thor seeing the sudden throw of the dagger just dodge the attack without any care for the world but by the sheer speed that Sigurd threw the dagger it manages to leave a small scratch on Thor's face, feeling the blood slowly pouring down from his right cheek Thor was slightly shocked but that shock soon turned into a smile on his face.

Sigurd who sees the few second chances quickly charges toward Thor in that moment Thor was in shock at the damage on his face, Sigurd takes this chance to let out a slash toward Thor's neck but that attack was soon found out by Thor who dodge the attack by relaxing his back, and made him fall behind. Thor then swings his body again dealing a deadly right punch to his liver of Sigurd, that punch alone manages to send him back toward the wall.

Sigurd who took the punch head was now heading toward the wall as he was about to hit his body with the wall, he quickly rotated his body turning his entire body upside down for his feet to land against the wall. With a quick chant, multiple unknown scripting began to appear in front of him the script soon began to turn red, and fire ignited from all the script. Focusing his muscle on both his feet Sigurd soon launch himself toward Thor, but this time with the aid of his fire Rune he manage to cloak himself.

The God of thunder who has seen this kind of trick before responded to the fire by grabbing his giant hammer and swinging it to his left side, the sheer strength that the God of thunder used to swing the hammer manage to create a powerful force of the wind that not only blew away the fire but also some of the audience on the human side. As the fire was now no more all Thor could see is nothingness that caught his attention, but soon his instinct began to warn him that an attack was coming to this warning alone force him to turn his head around the arena to find Sigurd.

While Thor was busy searching for the dragon slayer were about, Sigurd, on the other hand, is now located above the God of thunder as he clenches his right fist hard with Gram floating in front of him. Taking a few seconds for Gram to be charged with his prana soon lighting began to spark on the edge of Gram, while this was happening the God of thunder was looking for Sigurd's location on the ground. Clenching his fist even harder he focuses most of his strength on the right hand.

"Strike the God, Gram!" Sigurd roared.

His fist soon made contact with Gram's hilt with the sheer power that Sigurd has let out from his right hand, he send Gram toward the God of thunder as Thor just noticed the incoming attack from above. Without letting Thor draws his hammer Gram then strikes Thor with the amount of prana that Sigurd had poured into it.

The sheer force that Gram had put on for the fight was shown by creating a big and powerful explosion, the arena was now filled with dust and debris from the impact that Gram has released. But as time began passed the cloud of dust also began to disappear both the God and human sides of the audience were met with the sight of Thor being badly injured by the attack.

A pool of blood was created below his entire body which was bleeding from every part of his body, a hole in Thor's left shoulder that hole alone manage to rip the flesh and bone but also destroyed the upper part of his shoulder, the damage that was dealt toward Thor not only shock at the God of thunder but also both the audience side and the Valkyrie sisters. The dragon slayer soon lands in front of the God of thunder once their eyes meet a smile slowly forms on Thor's bleeding face.

"Bastard, that strength is wasted by a human like you," Thor said with a smile of excitement.

"I don't think so lord Thor," Sigurd said adjusting his glasses. "As this strength of mine, is proof of how strong and resilient humanity can strive in the face of absolute danger!"

Raising both their weapons at each other they now had one goal in both their mind, and that is to win.

"Let's see, how strong is the God of thunder in this timeline," Gilgamesh said.

Disclaimer: I don't own Fate and RoR

Note: The first round of the crossover will be the God of thunder against the Nordic dragon slayer, I've my reason as to why I choose Sigurd for the first round rather than some of the servants that can be chosen but you can tell me if there any better or compatible servant to face against Thor because I'm planning to make a sequel about this crossover after I finished all six round.