Berserker

Zouken let out an annoyed sigh. His useless son managed to somehow screw up and failed to summon the Servant the head of the Matou family had picked for him. Indeed, the man who appeared out of the summoning circle most definitely was not Lancelot du Lac, the Knight of the Lake... That said, Zouken had to concede that the Heroic Spirit who has answered Kariya's call looked quite impressive:

The summoned Servant was easily seven feet tall and rather muscular man with messy brownish-red hair and some prominent sideburns. His clothes consisted of a white shirt with a red tie under a black waistcoat, as well as black pants with brown dress-shoes. Finally, while this unknown Servant possessed a rather ogrish face – whats with that prominent under-bite – his eyes, hidden behind some classy glasses, betrayed a very sharp mind.

Perhaps, this Heroic Spirit might actually be able to win the Grail War...

"Remember our deal, Kariya." Zouken spoke. "Bring me the Grail and I'll let Sakura free." As those words left his mouth, the Servant scowled for a moment, before schooling his features back into a neutral expression.

"Master, this man is terrible; Abusing children is not a crime I can forgive. Let me do this evildoer in." Berserker asked Kariya telepathically. The young Matou nodded slowly, before replying over their mental link:

"If you can do so without him having a chance to screw us over."

"I can end this in an instant, Master." The red-haired giant said in response. "All that I need is this man's true name." Kariya couldn't help but let a certain grin appear on his face. Just a couple of minutes ago he was fearful for Sakura due to his failure to summon the Servant his evil father had chosen for him, but now... now he might be able to free the girl from her Hell on Earth regardless of how well he did in this damned 'Holy' Grail War.

"His original and true name is Makiri Zolgen." Berserker nodded.

"Thank you." He said as a strange cross-shaped silvery knuckle duster appeared on his left fist. A moment later Zouken found the said knuckle duster pressed against his abdomen. Then the old master of worms found himself torn out of the usual reality and stuffed into an inescapable black void...

~/ *** \~

"...If you can't discern my identity even in the presence of my glory, then your ignorance shall result in you death!" Archer intoned arrogantly as a pair of golden portals appeared behind his back. He didn't get a chance to fire some majestic weapons from those portals, though, as a new character entered the docks-turned-battlefield. Much to everyone's surprise, this man wasn't wearing any visible armor and instead looked like a gentleman straight out of some classy club.

"Those armors, the patters on them look like something Mesopotamian. And the most known figure hailing from there is the fifth king of Uruk, Gilgamesh. The first hero ever celebrated by the humans. Are you him?" The unidentified Servant asked. The now-named Archer let a smile appear on his face.

"See this, mongrels!" He addressed to Rider, Saber and Lancer. "There are those in this world that still can understand my glory!" Unfortunately for him, the mysterious gentlemanly Heroic Spirit wasn't there to worship him...

"I see... Thank you for confirming your identity." The man spoke as a strange knuckle duster materialized on his left fist. "Now I can fulfill my Master's wish properly." And so he charged at Gilgamesh with some very surprising speed.

"If the death is what you wish for, mongrel." The now very annoyed golden Archer hissed. "Then I'll gladly put you down!" Several more portals opened behind him and an instant later the weapons from them were fired at the unidentified Servant. A second later numerous explosions tore up the area, obscuring the apparent-Berserker in a large cloud of dust and magical smoke.

For a moment it looked like Archer's Noble Phantasm had taken the gentlemanly Berserker out, but then the man exploded from behind the smokescreen, looking pretty much intact. Indeed, aside from having his clothes torn up a bit and a bleeding cut on his left biceps, he looked fine.

Gilgamesh certainly looked rather surprised by how this strange Servant managed to survive his barrage, but he wasn't going to let this surprise stand in the way of his justice. Four more portals appeared around the Berserker's expected path, the weapons in them ready to protect the world's true king and skewer the mongrel who dared to attack him.

The red-haired gentleman saw this and managed to stop his charge a blink of an eye before it would have spelled a certain death for him. Still, being force to dodge such an attack meant that he himself couldn't land a hit of Archer. The same wasn't true about the lamppost the King of Kings was standing on. And by utterly destroying that lamppost with but a single punch Berserker fully confirmed that he indeed was of that class, even if he appeared to lack the madness one would expect from him.

"You..." Gilgamesh hissed in barely-restrained anger as he gracefully landed on the ground several feet away from the wreck that was the lamppost he occupied moments ago. "You're making me stand on the same ground as you, mongrel?! I, who belong among the Heavens?! Your impudence has sealed your doom!" As those words left his mouth, dozens of portals opened up around him...

"Brain Grid Blood Battle Style: Form 74: Kreuzschild Unzerbrechlich!" Berserker announced while planting his left fist into the ground. A moment later several large cross-shaped shields that were seemingly made from blood surrounded him, intercepting the weapons Gilgamesh has fired at him. And while the golden Servant stared in surprise at how his kingly might was denied like that, the red-haired gentleman closed in on him.

"Gilgamesh... I hereby seal you." Berserker announced as his knuckle duster made contact with Archer's cheek. "Despise me. Forgive me. Resign yourself." He chanted an aria as mighty aura of magic surrounded the two of them. "I take these barbarous actions to protect the human world. Form 999: Ewigkeit Gefängnis!" Rings of blood-red magic surrounded the golden Servant's body, quickly transforming it into nothing more than an ugly demonic cross that fell onto the ground with a glassy clatter. Then the cross faded away in a golden mist.

None of the other Servants or their Masters present was able to utter a word: right before their eyes a completely-unknown Heroic Spirit took down the supposedly-strongest Servant of the Grail War. That was... something mind-boggling.

Berserker himself, meanwhile, appeared to in a telepathic conversation with someone.

"Please forgive me." He then spoke, addressing to everyone else in the docks. "But it looks like I can't be attending this marvelous battle of yours tonight anymore. This last sealing technique has put quite a strain on my Master and he now needs me by his side." With a slight bow, he turned around and walked away.

Berserker

True identity: Klaus Von Reinherz
Series: "Kekkai Sensen"
Age: 28
Sex: Male

Alignment: Lawful Good
Strength: A
Endurance: B
Agility: D+
Mana: C
Luck: E+
Independent Action: D
Magic Resistance: C
Battle Continuation: B
Mad Enhancement: E-

Noble Phantasms:
Brain Grid Blood Battle Style Master: He Who Hunts: A++, anti-unit (self). Klaus is a powerful and experienced blood breed hunter and possesses a large number of techniques that allow him to prosper in this field. The strongest of these techniques is "Form 999: Ewigkeit Gefängnis", which allows him to permanently seal away any target, whose true name is known to him. Grail treat this sealing as an irreversible death of the target. In addition to his blood techniques, Klaus also possesses superhuman strength, speed and endurance – the result of him being almost turned into a blood breed in his youth. Finally, due to being a blood breed/vampire hunter, Klaus gains significant bonus to his strength, speed, endurance and battle continuation, if his opponent possesses vampirism skill or is otherwise associated with vampires.