Fate Series One Shots

Berserker - Cú Chulainn (Alter)

The Mad King
King of massacre
His dark side
Cú Chulainn Alter

An Alter servant. To think I summoned an Alter servant...
Alignment—Chaotic Evil
Attained Nature—Ferocity
Inverted personality, cold expressions
High survivability despite his Berserker class

A Noble Phantasm truly attributed to the legendary lance Gáe Bolg, barbs explode outward and spread through the veins and arteries until they're basically a thorn bush. This attack costs his arm, breaking it off from his body. But, he can recover. He uses Rune Magic, he endures the pain.

"I forbid the use of your Noble Phantasm, Carnage Gáe Bolg, without an explicit command to do so."
"Okay Master..."

Though in blind madness for victory, I don't know why, but I wouldn't be able stand watching him tear himself apart.

I find my servant to be like a wild beast, a lion. A Berserker has a one track mind. He knows he is a familiar made to fight, so he agrees to every order relevant to combat. He finds his purpose to be to kill his opponents. He does without hesitation, who the opponent is no concern of his.
Luckily, I've actually tamed lions before.

What he believes. What he thinks...
Eyes are the window to the soul aren't they?

Gathering intel, I have confirmed all the masters have made it to Fuyuki. I have spent my entire day making the last of my preparations. I surmise that the last of the servant will be summoned very soon, hence the Holy Grail war will begin.
I have magic barriers, and familiars positioned in key locations and it's gotten late.

Homestretch for the day, four blocks from home, on a hill sidewalk and Berserker has been with me, dematerialized, this whole time. He hasn't said one word.
I can tell he's getting impatient for battle. To be honest, a servant could challenge any day now, even if all the servants haven't been summoned. Since I know the identities of the six other Masters, I can assume other Masters know of me, at least a couple of them.

I low key, really don't want to encounter another servant tonight or tomorrow. I'm pretty tired, damnit.
"Master!" I turn to my side, and Berserker is materialized in an instant. He's blocks the sword of another servant.
"Assassin." I back up quite a bit, as to not be in Berserker's way. There is no reason to allow him to start fighting because he already has. But, we've also been over our battle strategies so, we are prepared.

I don't currently know where Assassin's Master is, but as a mage I take action. While the clash of their weapons continues, I use rune magic, and write on the ground that glow then begins to spew fog. Next priority is to check for Assassin's Master.

I write more runes that produce three familiars to find Assasin's Master. Two fly and the third travels on the ground. I cast a spell that surrouds a large area, outlined in runes that glow then fade when I cast it, starting at me, traveling out. A basic barrier. Any magical disturbance will stay, and only be seen inside, the servants, the fog and my other familiars.

Berserker basically deforests the small area of trees hunting down Assassin, but he is gaining ground against him, meaning he's winning. Suddenly all of my familiars are smashed, each in succession, and I rush toward that direction.

I find Assassin's Master, and write runes in the air that cast fire at my target.
"You're mine, Master of Assassin!"

Man, they Holy Grail War hasn't actually started yet and Assassin and his Master are already defeated.

"I realize you most likely didn't actually do it for me, but you saved my life from Assassin. Thank you Berserker."
"Hmph." He grunts with his arms crossed as her turns around and dematerializes.

——————

"What is this beast's desire? It is not to survive. It is to keep sprinting. A beast eats meat for the sake of survival, not for the sake of sprinting. For this reason, this Cú Chulainn discarded even the futile desire of "to eat". Just quickly. Just at a distant place. Just for no meaning. To use up all his strength, looking for and believing in a goal of finding a place for himself to die."
(TYPE-MOON Wiki)

——————
Third Person POV
She stands at her bedroom window looking down toward her backyard. In the middle of the night, she watches and wonders about her indifferent servant.
She stood at her window for hours before going down to him.

Cú Chulainn stands leaning against a tree with his arms crossed and eyes closed. As his Master approached he glanced down at her apathetically before looking off in another direction.
"Is it time to battle again?"
"No, it's way too early in the morning for me to go and do that." The servant grunts in response.

"What is it?"
"I seems inconvenient for a human to be up this early."
"Hey, you're being way too uptight about this." She informs him.
"Hmph." He dismisses.

The young woman sat against the tree.
"Come here." She tells him.
"I'm already right here."
"Come down here."

The Berserker hesitantly sits down beside his Master. She takes him, forces him to lay down in her lap and pets the side of head.
"Relax, would you? I know what it's like to think your only purpose is to be another's blade." Cú Chulainn doesn't resist and stops being tense. "I promise I'll do everything to keep you safe, so please place trust in me."
"You have our role's reversed Master."
"Seems so, my lion."

——————
First Person POV

I open my eyes to the sun blinding me back into closing them.
I feel cradled.

I'm unsure of the time, but the sun is rising and I am now sitting in Berserker's lap sideways with his arms around my waist holding me against him.
I only lay my head on him.

I stand up abruptly looking south.
"Master?" He stand up and looks down with his same expressionless look, but I can see the emotion in his once cold eyes.
"A servant coming in from the south, southwest eta: 1 minute 40 seconds."
"Leave them to me." He turns to go.
"Berserker." He turn his head to the side in acknowledgment. "Thank you."
"Hmph." He bolts off, but I could have sweared, I saw him smile.

Took a lot of facts from here:
http://typemoon.wikia.com/wiki/Berserker_(Fate/Grand_Order_-_Cú_Chulainn_Alter)