What would happen is Saitama from one punch man accidentally teleport into Percy Jackson universe and have a daughter with the god of the hunt and the moon Artemis

Ranma Saotome, a martial artist for fun, faces crazy rivals, crazy brides, monsters, and a perverted old man, lucky that after years of training he has become the strongest man... and the strongest woman.

Lloyd Belladonna has moved in to live with his Uncle Saitama, the stronget hero in the world that nobody knows, with the purpose of becoming a hero just like his uncle, and he has the super strength to back him up to go against dangerous monsters and some lovely ladies falling for his innocent-heroic spirit while his uncle saves the day with ONE PUNCH! Triple Crossover. Harem.

Goshikida Kaito's goal is to become a number 1 hero by becoming a Sentai. But to make it up top, he has to become stronger. Come and see Kaito and his team travel around the country to activate their Sentai Gears to become a better and stronger team.

After battling the so-called "God" and destroying the universe with Zero Punch, Saitama was left drifting in the void until he fell asleep and merged with the soul of sixteen-year-old Ohma Tokito (his powers, much to his disappointment, also transferred with him to his new body)

After a Mysterious-Cube falls from the sky, Class-1A finds themselves transported to a strange alternate-universe, and until they can return home to stop All-For-One and Shigaraki, they must train under the Class-S Heroes of this Other-World, and grow strong enough to win the Final-War that awaits them... (An Alternate Take on Lumpeistbark3's CYA: What Defines A Hero Series)

Stranded in an unknown world, but not alone, Saitama and his friends lived their lives in a strange world. They found happiness and peace, but an old evil returned, birthing new evils and challenges for the next generation. Co-written with i4md347h, the author of The Hunter Amongst Villains. Current Progress: VOL.7: COMPLETED. Now available in AO3 under the pen-name OldWanderer.

Two humans seen as Monsters by everyone, one seeks to be loved and seen as a human by everyone and the other seeks to be feared and seen as a Monster by everyone. But despite there differences they both been wearing a mask to hide there true self. In order for them to overcome there obstacles they must both face there true selves.

It's a fanfic where Naruto, has his parents alive, has a brother and two sisters, is neglected, and becomes strong... but in a very different way, and with elements of One Punch Man.

This Fanfic idea comes from a dream I had. The best Summary I have is, Ryuko did Saitama training and chaos to the canon. Ryuko personality is fusion in between Ryuko and Saitama.

The world has been incinerated. The last remnants of humanity are on their last legs, unable to fight against those who wish to see them annihilated. To aid them, one man will cross even the boundary between worlds. A Paladin of Justice, a man whose mere presence comforts the masses and silences their cries. He is King, The Strongest Hero.

The Justice League are happy that the world has now tons of heroes to protect the world, but now bigger threats are coming and danger is at every corner. However, one certain hero gets the champions of Earth by surprise, a bald guy with a cape which might have powers that could rival Superman. Can Saitama and his friends get along with the heroes from the past?

Izuku Midoriya is the younger brother of the famous Psykick Sisters Tatsumaki and Fubuki. Both women have powerful quirks that made them some of the most powerful heroines in all of Japan, while he started out having no quirk. However fate was waiting for him, as he works hard and soon meets up with the Number One Hero All Might, also there is a bald hero who appears from time.

One-Punch Man vs Invincible. The Dominator of the Universe and Scourge of the Twin Galaxies have finally found a worthy battle worth going all out!

A reincarnator with a cowardly personality, but heroic heart is thrust into King’s body with the knowledge and ability to use Haki ! Monsters beware. One piece crossover! OpKing! GamerKing!

The Martial Arts Expert, Bang, get reincarnated in Naruto World without memory, but regains them after reaching his nineties. Now he is on a mission, to not only teach the youth, but also himself after his past failures.

When Demons and Villains of many pop up out of nowhere, The Hero Association is forced into a conflict of Gods and Demons. The Doom Slayer is faced against Demons who are now stronger, faster, and deadlier. In this story, The Slayer will be tested, trialed, changed, loved, hated, scorned, recognized, insulted, and fought through the world of One Punch Man! Rip and Tear.

How did it come to this? How in the world did Tatsumaki end up with an adopted daughter in a completely different world? She doesn't even know how to return home for god's sake. She only knows that she will be a better role model to Eri than she was to Fubuki.

Izuka Yagi was neglected and abused by her family and friends for being quirkless, and after finding out the truth of her father quirk she was met by a extremely powerful being that gave her power, now she will take revenge on this cruel society with her monster army that she created, she will be known as Psykos First story

My firsy story in fanfction In this story Izuku didn't meet All Might after the slime villain incident, so he started training and achieved unbelievable results, in short it's a One Punch Deku story.

Akemi Homura se opuso al destino, desde que encontró un motivo para levantarse, no paró de luchar contra las cuerdas que la atan. Mami Tomoe, aceptó parcialmente su destino, ella vivió en soledad y solo se dedicó a luchar. Dios, es el dueño del destino, es el creador de las 'casualidades'. Él ahora va a escribir un nuevo destino para ambas.

After his Marvellous victory and saving the Shingeki No Kyogin Universe, Saitama is set into new adventures against Demon Lord Rimuru Tempest. Will they be able to handle more than just 1 of his punches? Not many actually.

[I have a similar story in mind but it's going to be different, this was a version I had in mind but I discarded it.]. What if the Skullgirl, Marie, was like Garou? After her defeat to the point of death, Marie returned to life as an Undying but retaining a small percentage of the Skullheart's power. Now with his new lease on life he is going to finish what he started...

Issei Hyoudou finds himself at home... Or not? How will he make the heads and tails of his current situation? A companion story to NEO, which contains spoiler elements here and there. Read at your own risk; rating may change in future.

After sacrificing himself in the final fight against GOD, Saitama disappears from his world. Picked from the space between dimensions, he is reborn in an unknown world called Remnant. He decides to do the only thing he knows how to do - to become this world's version of a Hero, a Huntsman. How will he change the fates of those in Remnant? Only time will tell...