Prologue: The Sucesor of the snake
disclaimer: Neither Harry Potter or league of Legends belong to me.
In the land of the death a solitary man dressed with black clothes and a dark green tunic was seeing the state of the magical world with absolute rage "After all our sacrifices and effort our dreams and work is only a shadow of it's former glory" mutered the man with barely contained comptent because all the blood, sweath and tears that they put in the creation of Hogwarts and the organization of british magical community was basically destroyed for the fools in the powers the so called 'Purebloods' who in the pursuit of the aberration that become his ideals destroyed all the work that he and his friends and allies did.
"And don't get me started with my supposed 'heirs' " Commented him after seeing what the last one of his descendent did. The so called Lord Voldemort, hmp a common street rat possing as a king a pursuing the halfbloods when he was one and worse the fool was so arrogant to don't think that the parents of the child won't have somekind of defenses ready for him, so after seeing him blow away thanks to his own curse he noted something interesting in the black haired baby scar that was formed by the curse "Oh this is rich, that fucking idiot fucked up and transformed that boy in a horcrux" said the man with mocking driping from his voice. Because if there one thing you can have sure about Salazar Slytherin is that he will mock you if he consider you an Idiot.
"I see you're eenjoining yourself Salazar with the latest failure of your bloodline" said a femenine voice behind him, he didn't need to face the person to know who was. After all she always come to taunt him with the fact that the work of the life of his friends and him was a mockery of its former glory.
"Nothing of concern for you Lady Thanatos, I'm only contemplating the mockery that became the dream of my friends and i" answered the founder of Hogwarts with barely contained rage after hearing the mocking tone used by the goddess. After all she always did that since the day of his death so many centuries ago.
Thanatos only smiled wickedly because very soon the wretched Peverell bloodline will pass to the oblivion and that way no one will mock her again, after all no one cheats death. Salazar didn't need to see the goddess of death to know what's she was thinking.
"I won't let this people to die for the whims of a scorned goddess, I will save them somehow and maybe that way my legacy won't only cause strife in this world" thought the wizard with a meditative face when a plan was beginning to form in his mind.
So without missing a beat the wizard leave the place to execute his plan, without noticing the goddess of death smiling sinisterly behind him "So it's begins" murmured her while looking at the baby with a expression of barely contained lust "you will be mine boy, after all while you will be a king amongs men I'm a goddess and you will learn to adore me as your one true queen" in that moment her expression turned sinister "after all you are destined to walk alongside me 'master of death' " murmured her after remembering the visions of the future that she saw.
/In another part of the underworld/
James Potter walked the dark and lonely roads of the underworld with a peace of mind that few spirits would have possessed after all with the knowledge that the cloak was out of reach from his family in the hands of dumbledore sparing them of the curse of the hallow and saving their lives and while it hurts to know that he won't see his family for a long time the price was worth. Indeed you can say without doubts that James Potter was a man without regrets in the land of the dead.
"You're a lucky man James Potter" said Slytherin appearing from the shadows "and I congralate you because you're the first of Peverell bloodline that have come closer to breaking the curse but unfortunately isn't so easy" finished the founder with a serious expression.
That almost shattered the mind of the late Potter, but using all his remaining willpower he decide to inquire the man about it because if he knew about the curse that mean he was also part of the Peverell bloodline "who are you?" Asked James making Salazar smile.
"Like yourself I am a Peverell descended, but if you want to know my name is Salazar Slytherin founder of Hogwarts, soul mage extraordinary and the wrongly named creator of that rubbish known as the 'pureblood doctrine' at your service" answered the man with a smile on his face after seeing the stunned expression of the man.
That certainly surprised the late lord Potter because of all people he could have expected to be waiting for him he certainly wasn't the late founder of hogwarts be talking to him about the curse that affected his family. But if he know something about the curse he will listen to him "what do you know about it and why you said that my family is still affected by it" asked him.
Salazar smiled at the question because he was right about the man. He wasn't an idiot "simple I want like you break this curse because the goddess of death have caused enough suffering in our families" said him to take a serious expression "besides Thanatos the goddess of death have taken a strange interest in your son and that never ends well for the person of interest"
In that moment the founder took a self depreciated smile while continuing talking "after all I was the last one who attracted her interest" That made the man pale considerably because he knew that the fates of his son and daughter would be more darker than he ever imagine.
"And what you recommend me to do them? Because I'm already dead and i doubt that I can do something about it" said him angry but Salazar calm him down explaining him his plan.
"Relax Lord Potter because I have a plan to both save your family and saving us if this cursed destiny" answered Salazar with a serious voice "But i need your help for it" that caught the attention of the Potter patriarch because in that moment he discovered why the spirit of the late founder was talking with him. He needed his help for something.
"what's your true objective Lord Slytherin because i doubt that someone like yourself would waste your time talking with a perfect stranger" Salazar smiled pleased because he choose well. This man wasn't an idiot.
"Is simple I need your help to stop this cursed cicle and clean house in the magical world, because those fools that are doing all kind of crime in the name of my so called ideals are going to destroy our world and you liked it or not your son are in the middle of it" explained the man truthfully, after all it was useless lie to him because they are already dead and he would gain more speaking the truth.
James noted that his companion was speaking the truth so after thinking for a few minutes his sighed and answered "Ok i accept. What do you need from me" Salazar Slytherin for the first time in centuries smiled for real before answering.
But without both men knowing it their pact wouldn't only change the fate of their world but of another one more magical and dangerous than their own.
/Moments later in the Living world/
In the mansion of the potters a strange phenomenon was happening because a great quantity of magical energy was entering in the body of the late james Potter causing it to burn away in blue flames destroying it to later begin to form the human body of Salazar slytherin who fall on the floor with uncontrollables fits of laughter.
"I am alive... I am alive! oh sweet merlin i am alive!" screamed with ecstasy the man before calming himself and with some effort going to the room where were the the three peope who he come to save.
Once there he saw the unconscious body of lily Potter and couldn't help but congratule in his mind James Potter for marrying such beautiful woman and after making sure that she was alright he went to the crib in which was the infant Harry potter who after see him smile to salazar causing the man to chuckle.
"You are a brave little boy and without doubt you will one of the few that will rise above the others like my friends and I" say Salazar to the baby before taking him and going towards his mother "Now let's take your mother so we can go to our new destination away of the pathetic trash that now control the Magical world"
Once besides Lily he levitate her and chanted the spell who would change the course of story in two worlds forever "Kaleidoscope!" in that moment the 3 of them were engulfed in a blinding light sending them towards the world that Salazar discovered during the last days of his life, the Realm known as Runeterra.
/2 days later in the Slytherin sanctuary in Runeterra/
The first thing that Lily Potter noticed once wake up was that she wasn't in her bedroom but in another one finely decorated with a handsome of her same age group with, black slightly messy hair, dark blue eyes dressed with black clothes and a dark green tunic feeding Harry. In that moment everything returned to her mind, but before she entered in a panicked state the man noticed that she was awake and went to calm her.
"Relax Lady Potter you and your son are safe i manage to save you two after that mongrel was destroyed by the blood wards" that manage to calm her down, noticing that salazar give her harry that after noticing being in the arms of her mother began to giggle happilly making her smile a little.
"Thanks for your help stranger but can you tell me who are you and were are we? asked her making the man smile a little because it was obvious that this wasn't an ordinary woman. Any other person would have broken down after the last events tht happen to her.
The Hogwarts founder smiled in a trollish way, after all this was going to be soo fun "Of course my lady allow me to introduce myself: I'm Salazar Slytherin, cofounder of Hogwarts, master soul mage and the unfortunate so called creator of the aberration that is the pureblood ideology" that make the poor young woman pale and cause the man to laugh at her "relax lady potter i won't hurt either of you because contrary at what you may believe i don't hate half blood and muggleborns"
That surprised the young woman because she never expected that the infamous Hogwarts founder were so easy going and flippant but them she rememnbered wat he said about James so she asked him about it.
"What do you mean that you promised James to protect us and that about you don't hating the muggleborns?" he took seat in the chair besides the bed and begin to explain everything.
Once he ended explaining things to the woman about how he and his friends decided to found Hogwarts, how he and Godric were friend when the other was a muggleborn son of a knight, of his love for Rowena, the cautioness he have towards the muggleborns thanks to the witch hunts and how he went in search of a way to stop the curse of the hallows and ending in a new world,his meeting with James and their plan to destroy the curse and change the magical world and how they went to the world of Runeterra to prepare for their eventual return.
"And tell me will you help me Lady Potter to change to the better our country and stop the whims of a scorned goddess" asked him already knowing the answer. Lily after analizing all the information gave her answer.
"I Accept your offer Lord Slytherin" the man smiled to her before kissing her hand
"It would be a real pleasure to work with you my lady" and after daying that he bring to the room a great variety of foods "But first let's eat and rest because we have too much to do tomorrow" said him causing Lily to giggle.
/The underworl throne room/
"How dare that man to take him away from me!" screamed the raging goddess while was destroying everything in the room with her bare hands. 2 Days have passed since she saw a Revived Salazar Slytherin take the man she choose to be her consort to another world and since them her rage haven't appeased "You will pay Salazar Slytherin for taking my consort away from me!" raged the scorned goddess before finally calming down.
"This isn't no problem i only have to begin to search in the universe where they are and once i find them i will make sure that the suffering of Salazar Slythering become legendary even in hell" muttered her with a slight psychotic look on her face while beginning her search across the universe for his prey.
Author Notes: And this is it, tell me what do you think of this story is good or bad because this is my first harry potter story in english. Well in referent to this story Harry will face many enemies and obstacles during his life and for the pairing will be harryxmulti.
Next chapter is a time skip and Harry meet his first friend and is chosen to go in a jourmey that will change his life while Lily and Slytherin begins to prepare thing for when is time to return.
PS: If anyone wants to imagine Death/Thanatos she looks like Cinder Fall from RWBY but with the dress black.