Roy Mustang Template in Harry Potter

MC gets transmigrated to a Harry Potter world with Merchant System

Tomas_Vega_2683 · Book&Literature
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22 Chs

Gideon Selwyn and Cecelia Crouch

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"I lost my pawns, my knight, my rook, my bishop, and even my queen. But, it's not checkmate, just yet. But I never feel more human than when I'm fighting real monsters."

Roy Said as he was on the ledge above the door which the Asylum Demon was guarding, and that the Asylum Demon was directly below him.

"Burn in hell you Fucking monster!"

Snapping his fingers, Roy used up almost all his mana Inceniration the Asylum Demon in a torrent of fire. After a second shot of alchemical fire the Asylum Demon was burnt alive.

Once Roy dispatched the Asylum Demon, he dropped

-2X Awakening potion: Triggers awakening of a bloodline with 70% Fatality.

-2,000 MSP

-High Wall dungeon key

[You can level up!]

[You can level up!]

[You can level up!]

Once Roy finished up with the Boss, he was kicked out of the dungeon and appeared back where was once was. Only a few minutes passed by when he spent hours in the dungeon.

Raising 3 more levels, Roy used the 21 Attribute points and distributed 9 to Attunement, Raising his mana to 200. The remaining 12 points he put on Arcane, increasing his magical power. For perks, once he reached level 6 he received new ones.

-Fortune Finder Lv1: Increase item quality discovery by 10%

-Scrounger Lv1: Increase item drop rate by 10%

-Sneak Lv1: 20% harder to detect while sneaking.

-Lone Wanderer Lv1: When adventuring without a companion, take 15% less damage and Equip Load increases by 10.

-Iron Fist Lv1: Punching attacks do 20% more damage.

-Big Leagues Lv1: 20% more melee weapon damage.

-Enchanter Lv1: Enchantments are 20% stronger.

Roy chose Lone Wanderer Lv1, increasing his Equip Load by 10 and taking 15% less damage. VANS Lv1 and Awareness.

Without much thought, Roy chugged down the Awakening potion, the next moments he began coughing blood as the potion was quickly killing him.

A minute later his body turned to dust as Roy reappeared not too far from where he was. He then chose to drink the second potion, resulting in him falling to his knees and feeling his blood boil. Vile-looking dark substances started being expelled from all of Roy's skin.

Waking up later a few minutes later Roy received a system notification.

[Congratulations, the Host has awakened dormant Black blood traits The Black Madness and Parselmouth]

[Trigger ability- The Black Madness: Increase Attunement, Arcane, Mind, and Intelligence by 40%. Decrease Vitality, Strength, Perception, and Faith by 40%]

[Pasive ability- Parselmouth: User can hear and speak to snakes]

Activating The Black Madness ability, Roy took a look at himself in a mirror, he saw that he looked like a madman. Turning it off he saw that his face returned back to normal.

Using VANS Roy found the tracks of the ones that killed the original Roy Mustang. Taking his broom he cast the Disillusionment Charm and followed the trail by VANS to his targets into some abandoned woods. The idiots were partying and getting drunk dancing around the bonfire, while he was flying in the night.

"Can't believe I let that muggel born touch me!"

Said Elizabeth gauging feeling sick at the thought that she slept with Roy.

"Come on Elizabeth, did you really need to sleep with that disgusting muggle, you should have told us sooner so we could have saved you from that muggle."

Said Mavros Flint as he took another sip of alcohol.

Flint couldn't tell what truly happened next, his vision was blurry from all the alcohol. He didn't even remember where he was, as they all were set on fire.

Trying to escape he apparated leaving his leg behind, and left his friends, knowing as Deatheaters they would understand that chose to save his life. His world came to darkness as Flint apparated at the bottom of a lake.

[You can level up!]

Evan Rosier and Lenard Crabbe were burnt to death. Elizabeth's wand, hands, and feet were burnt, making her fall to the ground writhing in pain as a criple.

"Any last words whore?"

Roy revealed himself as he was about to snap his fingers to burn Elizabeth's body, she cried out to stop him.

"Stop! You can't kill me, I'm carrying your child!"

Roy stunned Elizabeth, turned the corpses into ashes, then he put a ring in his Mokeskin pouch and apparated out of the area.

-Black Manor-

Arcturus Black sat in pain managing the family finances that were above and below the board. Reading through various letters and missives from allies and foes alike, he wrote back to those whom he deemed worthy.

With quiet pop Kreacher's arrived speaking in his broken English elf talk.

"Lord Master Black. There be a filthy mudblood stranger at the property line, he asking to meet with you."

"Who is it?"

"Kreacher isn't knowing, Lord Master Black."

The house elf grabbed his ears in frustration.

"Kreacher's just knowing that it's emitting Black family magic. He's having a ring of the family though."

Arcturus frowned. There weren't that many Family rings that were not in the Black vault, and of those the only ones that weren't unaccounted for were.

"Is it Sirius?"

"Is not the blood-traitor, no."

Arcturus's frown deepened as he began tapping his finger against the desk. Sirius would probably send someone to his doorstep with his ring as a prank, it wouldn't be entirely impossible if Sirius did that.

Regulus's ring was with him at Grimmauld Place. Andromeda had summoned her ring into her father's rear when she'd been cast out, that girl was still as vengeful as ever.

Bellatrix would sooner die than let a family heirloom fall into the hands of someone else. And Narcissa's ring had been returned on the day of her wedding. The heir ring was still in Orion's possession.

It couldn't be a fake, not since Kreacher had been the one to announce its presence. The beast might be a vile little servant, but he was as fanatically loyal towards the Blacks as possible. 

Soon Kreacher vanished and Arcturus freed his wand from the head of his cane. He threw open the front door and stepped out to find Kreacher's head snapping back and forth between himself and a strange boy who was the spitting image of him when he was young.

Arcturus stared down at the stranger who could've practically stepped out of his memories. He was a clean-shaven young man with dark eyes, and dark hair worn casually unkempt, falling over his eyes. Had he been properly dressed, and properly groomed, he would've been the spitting image of him, down to dark obsidian eyes.

"Who are you?"

"Roy Mustang."

'Where had he heard this name before? It was at the tip of his tongue.'

The boy bowed a perfect forty-five degrees and threw out his right arm to show he held no wand. The only thing strange about it was that he had a bound girl by his side.

"Son of Gideon Mustang and Cecelia Mustang. Formerly known as Gideon Selwyn and Cecelia Crouch, Before they got kicked out of their families for being squibs"

'Ah, so this is the grandson of my little sister, Dorothy who married into the Crouch family. I let her keep that ring if things went sour with the Crouch family. Didn't expect her to give it to her daughter who was kicked out for being a squib.'

"What do you want boy? You know you can't claim anything with that ring since your mom was kicked out of the family."

"I just need you to perform a magical paternity test for me on this girl."

Arcturus narrowed his eyes at the boy and looked at the stunned girl lying next to him. 


"I won't get help from the goblins because too many questions will be asked Even if she's a half-blood."

It seemed he had a brain on his head, then to try to get help from the Goblins, who would probably sell the information to the highest bidder.

"Kreacher. Get me a Family bloodline test and a paternity test parchment. Also, get the boy cleaned and clothed, then bring him to my study."

"Y-yes, Lord Master Black."

The house elf grabbed hold of the hem of the boy's robe and they vanished with a pop. Arcturus held back a groan as he turned on his heel and headed back inside, thoughts swirling around his mind.

'It would take more than a signet ring to prove the boy's blood, but that could still be taken care of simply enough. If the boy really was the grandson of one of his baby sisters then it could change everything.'

'Walburga and the others would throw a fit, if he tried to bring back the son of a squib. The worst part is, his the child of two, but he could handle them. Even if the boy caused a rift in the family, so long as he didn't swear off women like Regulus had or spit in the face of his betters like Sirius, he could be the boon that the family had deserved for decades.'

It all depended on just how much Black he was.


Arcturus found his thoughts interrupted by a much cleaner Roy. He was now wearing one of the old military uniforms he used when he fought Gellert Grindelwald's forces. A traditionally blue overcoat, pants, and black boots with a yellow forager.

RACE: Human/Wizard 

NAME: Roy Mustang


Vitality: 5

Attunement: 20

Arcane: 40

Endurance: 8

Vigor: 5

Resistance: 2

Strength: 4

Dexterity: 8

Perception: 10

Skill: 8

Mind: 10

Intelligence: 10

Faith: 5

Luck: 4

-Base Power 

Health Points: 200 +1 Regen/Minute

Mana: 80 +1 Regen/Minute

Stamina: 40 +2 Regen/Second

Equip Load: 16

Poise: 1

Item Discovery: 4%


Physical Defense: 8

Magic Defense: 18

Fire Defense: 38

Cold Defense: 18

Light Defense: 8

Dark Defense: 8


Bleed Resistance: 6

Poison Resistance: 6

Curse Resistance: 6

Toxic/Plague Resistance: 6

MSP: 2,000