Summary: (Y/n) Black, son of Sirius Black and Loréna Black née Sertrox, is a pureblood wizard living in the United States after a letter from his father he makes the decision to return to the United Kingdom and continue his studies at Hogwarts for its fourth year.
At the same time Hogwarts and the British Ministry of Magic are preparing a big tournament.
And the Dark Lord regains his strength and sets in motion a plan to recover a new body.
OC x Multi/Harem.
Powerful OC but not a Gary Stu.
I am not an English native speaker so I am sorry for the mistakes.

Bio, timeline and harem

(Y/n) Black is an English pureblood wizard who lived in the United States, he is transferred to Hogwarts for his fourth year.

Born two days before Harry on July 29, 1980 (which means that he could have been the chosen one of the prophecy in the same way as Neville), he has black hair and gray eyes.

His parents are Sirius Black and Loréna Black née Sertrox.

The Sertroxes are a pureblood family descended from Salazar Slytherin but also Rowena Ravenclaw, (Y/n) will prove to be a Parseltongue like his mother. He is also a natural Legilimens and was trained by his mother in Occlumency. He also possesses the gift of Oneiromancy.

He became heir of Slytherin family on the death of Tom Marvolo Riddle.

His mother fled Britain with him upon learning that the Dark Lord was looking for the Prophecy Child who could be (Y/n), she was warned by Bellatrix LeStrange née Black in a moment of lucidity . She did not want to return to the UK due to Sirius' imprisonment, she will become Ilvermorny's Defence Against the Dark Arts teacher.

(Y/n) grew up in USA; he study in Ilvermorny in the house of the Horned Serpent.

During his second year, he participated in an exchange program with the school of Uagadou where he learned in particular to rely less on his magic wand, to become an animagus and to make great progress in transfiguration.

(Y/n) is gifted on a broomstick but has never integrated a Quidditch team, he is a good student although he only does the minimum in the subjects that interests him little; he is a good (very good) duellist with a good instinct.

(Y/n)'score at the end of the third year:
Herbology: Acceptable
Defence Against the Dark Arts: Outstanding
Transfiguration: Outstanding
Potions: Exceeds Expectations
Charms: Exceeds Expectations
History of Magic: Acceptable
Astronomy: Acceptable
Arithmancy: Exceeds Expectations
Study of Ancient Runes: Outstanding
Care of Magical Creatures: Exceeds Expectations

In his third year he learns his father's escape and at the end of his year he receives a letter from him.

In a dream (Oneiromancy) he learns a Parseltongue spell for summon to him Salazar Slytherin's wand

(Y/n) is a gray wizard, he is not afraid to use all forms of magic even the darkest; he also has great magical potential.

(Y/n) has two wands, a wand in Red Oak and Horned Serpent horn, 30 cm/11,8" flexible. And another that belonged to Salazar Slytherin (Snakewood 33cm/13", Basilisk horn), he also has a firebolt sent by his father and a magic dagger belonging to the Black family (which he knows how to use).

Timeline:
-1970 start of Voldemort's reign
-September 1971: Sirius Black and Loréna Sertrox go to Hogwarts for the first time.
-End 1978 Sirius and Loréna are married
-29 July 1980 birth of (Y/n) Black
-January 1981 After agreeing Lorena and their son flee to North America while Sirius remains in the UK to continue the fight against Voldemort
- November 2, 1981 Lorena learns the Potters 'deaths, the murder of Muggles and Peter Pettigrew, and Sirius' incarceration (she doesn't believe for a moment that Sirius is guilty). And the "death" of Voldemort.
-July 29, 1991: (Y/ n)'s 11th anniversary
-September 1, 1991 (Y/ n) go to Ilvermorny for the first time, he is sorted to the house of the Horned Serpent and received his first wand in Red Oak and Horned Serpent horn.
-29 July 1992: (Y/ n)'s 12th anniversary his application for the exchange program with the school of Uagadou is accepted.
- September 1, 1992: (Y/n) go to Uagadou
-In 1993: (Y/n) becomes an animagus.
- End of June 1993: (Y/n) returns in the United States.
-29 July 1993: (Y/ n)'s 13th anniversary
-July 30, 1993: (Y/n) learns that his father Sirius Black has escaped from Azkaban.
- September 1, 1993: (Y/n) returns in Ilvermorny
-June 15, 1994: (Y/n) and Loréna both receive a letter from Sirius
-June 16, 1994: Through a dream (Y/n) learns a spell allowing him to make Salazar Slytherin's wand come to him, in the evening he uses this spell and retrieve his ancestor's wand.
-18 June 1994 after a discussion with his mother (Y/n) decides to return to UK and continue her studies at Hogwarts; his mother cannot follow him for the moment.
-September 1, 1994, (Y /n) go to Hogwarts.

(Y/n) Harem:
Hermione Granger

Daphné Greengrass

Nymphadora Tonks

Bellatrix Lestrange née Black

Fleur Delacour

Luna Lovegood

Tracey Davies

Susan Bones

Pansy Parkinson

Narcissa Malfoy

Iris Potter

Ginny Weasley

Additional informations

(Y/n)'s Animagus form:

A Dire Wolf (it's a middle ground between a magical creature and a non-magical creature; it's also a very big dog like daddy Sirius).

(Imagine Ghost from Game of Thrones and (Y/n) has the same ability to be silent, for the size it is between the size in GoT and the size in the books)

(Y/n) also has a female black owl with amber-golden eyes. (One of the same species Sirius uses to send a letter to Harry).

And as a familiar the ONE and ONLY KING GHIDORAH

It's a joke that would be way too powerful. (But that would be very cool)

More seriously it's a female Horned Serpent named Kisara (not sure of the name):

(Imagine her white rather than black)

As we do not know the abilities of a Horned Serpent, I therefore decided on his powers:
-Invisibility
-Fly
-Project lightning through her gem on her forehead
-Size change
- Deadly venom (not as powerful as Basilisk venom)
(it doesn't seem too bad)

(Y/n)'s Horned Serpent is 8, 2 feet long.

Other important characters may have Animagus form and/or a magical creature familiar, I haven't made up my mind yet but don't be surprised if that happens.

Harry Potter will become Iris Potter and will be part of the harem, she keeps her mother's eyes and her father's hair and wears glasses, and these are the changes that this implies:
-Severus still hate her but less than if she was Harry.
-Being a woman it seems logical to me that she is closer to Hermione than to Ron, so she is much more diligent in class (Hermione is always the first of their promotions but Iris is not far behind)
-Following Hermione's advice, Iris did not choose Divination but Study of Ancient Runes.
For the rest nothing changes and of course she is still the Chosen one.

After some thought Draco will remain a man that will make it easier for me to bring something up for the story.

All the characters "maybe" join the harem if I find a good way to do it, to which will surely be added Katie Bell.

I forgot to warn you but risk bashing it is possible that there is some bashing for Albus Dumbledore; Molly, Ron and Bill Weasley

Here is also (Y/n)'s titles:
Heir of the most noble and most ancient house of Slytherin
Heir of the most noble and most ancient house of Ravenclaw
Heir of the noble and ancient house of Sertrox
Heir of the most noble and most ancient house of Le Fay (in this fanfiction Morgan le Fay is the ancestor of the Black family)
Heir of the most noble and most ancient house of Black

The other characters belonging to important families also have titles, for examples: Sirius is Lord Black, Lorena is Lady Black and Sertrox, Iris is heiress Potter and Peverell (maybe even Gryffindor), Draco is heir Malfoy (and hoped to be heir Black) Lucius is Lord Malfoy et cetera.

I want to avoid doing a Gary Stu, so if I go too far don't hesitate to let me know.

I am not an English native speaker so I am sorry for the mistakes. If you see any errors please let me know.