OK K.O.! Let's Be Heroes Crossovers
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Christmas Gem & Pow Card Spirit by Lonely Fanboy48
The Christmas season has arrive and Steven Universe and OK K.O.! Let's Be Heroes are eager to show what they have in store together for the holiday.
Crossover - Steven Universe & OK K.O.! Let's Be Heroes - Rated: K - English - Fantasy/Friendship - Chapters: 1 - Words: 5,618 - Published: 12/1 - Steven U., K.O. - Complete
Helpful Teams by Determined Artist
During their school and another school's event K.O, Dendy, the triplets, and Webby are put on teams of two, their teamwork skills will be put to the test. 2017 Ducktales characters are used in this.
Crossover - DuckTales & OK K.O.! Let's Be Heroes - Rated: K+ - English - Friendship/Humor - Chapters: 1 - Words: 935 - Published: 11/18 - Dewey Duck, Louie Duck, K.O., Dendy
A Drunken Knockout Marriage by yoshi3000 reviews
Alcohol drowns your sorrows, get you reality warping powers, and get yourself married to a kickass martial arts mother. Wait, what! Kaze Gray will probably never drink again. Now, Kaze will have to up his skills to become a real hero alongside her and his step-son. (The first OKKO 'Drunk Marriage' Fic) (Carol/OC) (Crossovers) (Complete, sequel - "FusionFall Infinite")
Crossover - OK K.O.! Let's Be Heroes & X-overs - Rated: M - English - Humor/Romance - Chapters: 14 - Words: 30,489 - Reviews: 33 - Favs: 39 - Follows: 38 - Updated: 11/4 - Published: 8/8/2017 - [Carol, OC] Rad, Enid - Complete
A Hallow's Even with Madam Johanna by francisthewitcher reviews
Halloween Special! As Hilda goes trick-or-treating with her friends, Thomas and Johanna decide to spend their Halloween by staying a haunted mansion overnight while hunting some ghosts. It's supposed to be a simple and not-so-dangerous task. But instead they find someone who's willing to make a night they won't ever forget. Special Guest: Wilhamena from OK KO Heroes.
Crossover - OK K.O.! Let's Be Heroes & Hilda - Rated: M - English - Romance/Humor - Chapters: 1 - Words: 22,011 - Reviews: 4 - Favs: 12 - Follows: 7 - Published: 10/29 - Johanna, OC - Complete
Let's Head Back to School by Determined Artist
When K.O is in need of an item both he and Rad goes to Rad and Enid's old high school, Norrisvile high where something changes, and somethings stay the same. Though when trouble arises Rad would have to team up with the ninja of Norrisvile, solve it.
Crossover - Randy Cunningham: 9th Grade Ninja & OK K.O.! Let's Be Heroes - Rated: T - English - Friendship - Chapters: 1 - Words: 256 - Published: 10/6 - Randy C., Rad
La guía del viento, el agua y del amor by LaGataOtaku
Dendy, la protagonista, es una niña de entre 6-12 años que se muda a una nueva ciudad con su padres. Es tímida, un poco inmadura y bastante quejumbrosa, y no se imagina la aventura que está a punto de experimentar cuando ella y sus padres entren en un parque de diversiones abandonado. Ahora depende de ella madurar y aprender al lado de un misterioso niño de su edad. ¡Disfrutalo!owo
Crossover - Spirited Away & OK K.O.! Let's Be Heroes - Rated: K+ - Spanish - Fantasy/Friendship - Chapters: 1 - Words: 3,053 - Published: 7/22 - K.O., TKO, Dendy, Lord Boxman
Triple Threat by Ekroth Ekronicus reviews
King, Flashy Flash, and Amai Mask are brought into a secret facility and are each assigned to undertake a recon mission… in another world! A place where the civilians often resemble mysterious beings, and chaos runs rampant, how will these three heroes fair in such an alien world?
Crossover - One Punch Man/ワンパンマン & OK K.O.! Let's Be Heroes - Rated: T - English - Humor/Adventure - Chapters: 2 - Words: 12,538 - Reviews: 6 - Favs: 17 - Follows: 18 - Updated: 4/6 - Published: 4/5 - King, Flashy Flash, Amai Mask, Fink
Potential Investor by Karaifan16
Black Hat and his employees are coming to Voxmore to see if it's worthy to invest in. Prof. Venomous and Boxman went through everything to make sure it will go smoothly, but they overlooked one detail. It's the weekend, and that means it's time for KO to stay over.
Crossover - Villainous & OK K.O.! Let's Be Heroes - Rated: K+ - English - Humor - Chapters: 1 - Words: 566 - Favs: 4 - Follows: 5 - Published: 1/14 - Black Hat, Dr. Flug, Professor Venomous/Shadowy Figure, Lord Boxman
OK KO!: Let’s Beat Aku (Unfinished) by arditpjguy28
An OK K.O.! & Samurai Jack Crossover Novel
Crossover - OK K.O.! Let's Be Heroes & Samurai Jack - Rated: T - English - Chapters: 1 - Words: 34 - Published: 1/5 - K.O., Enid, Rad, Aku
Yin, Yang, Battle by Determined Artist
Au fic where OK KO characters in the Arc V universe. Yuya and K.O both have other sides of themselves who would rather do their own things then do as they say to the point that those sides ended up hurting those around them. One day when dueling, they both find out that they more in command then they realized. They agree to help the other out.
Crossover - Yu-Gi-Oh! Arc-V & OK K.O.! Let's Be Heroes - Rated: T - English - Friendship - Chapters: 1 - Words: 1,013 - Favs: 2 - Follows: 1 - Published: 9/19/2021 - Yuya S., Yuri, K.O., TKO
Ok KO: Raging Ralph by ReptileEdge reviews
The thirty foot mutant grey wolf, Ralph, gets transported into the universe of our favorite hero in training, and becomes a human after getting beaten and caged by P.O.I.N.T. He later, unwillingly, becomes a student and discovers Lakewood Plaza Turbo after he escapes. But can our favorite heroes turn this raging lone wolf into a hero, or will he remain as the monster he’s become?
Crossover - Rampage, 2018 & OK K.O.! Let's Be Heroes - Rated: T - English - Sci-Fi/Fantasy - Chapters: 13 - Words: 31,662 - Reviews: 49 - Favs: 22 - Follows: 16 - Updated: 8/23/2021 - Published: 9/9/2019 - K.O., Rad, Enid
A Little Help by Determined Artist
A little one shot drabble I made of a teen Dendy and Brief meeting and Dendy helping him out.
Crossover - Panty & Stocking with Garterbelt/パンティ&ストッキングwithガーターベルト & OK K.O.! Let's Be Heroes - Rated: K+ - English - Humor - Chapters: 1 - Words: 803 - Published: 7/19/2021 - Briefers R./Brief, Dendy - Complete
King: The Level Zero by Geek-Mytho
God granted me a new life to help him save the OK KO World
Crossover - OK K.O.! Let's Be Heroes & Cartoon X-overs - Rated: T - English - Adventure - Chapters: 4 - Words: 7,623 - Favs: 4 - Follows: 6 - Updated: 5/10/2021 - Published: 8/6/2020 - OC, Potato
Swapped Heroes by TheLastUnicornInOz reviews
KO and Izuku Midoriya, two kids who have dedicated their young lives to be training to be the best heroes in two societies where almost everyone is born with a power of their own. They each have their own journeys to follow and enemies to defeat. All of that is sent screeching to a halt when mysterious villains arrive, taking the two boys and swaping them between the two worlds.
Crossover - My Hero Academia/僕のヒーローアカデミア & OK K.O.! Let's Be Heroes - Rated: T - English - Adventure/Friendship - Chapters: 6 - Words: 15,063 - Reviews: 82 - Favs: 101 - Follows: 111 - Updated: 4/25/2021 - Published: 11/4/2018
KO Runs away from home by Finalcool720
K.O runs away from home to Zootopia after finding out his dad laserblast is Professor Venomous and leaves lakewood plaza and decides to embrace his life as a were-puppy living in zootopia to not deal with the truth but with the help of Judy and Nick he realizes its not that bad.
Crossover - OK K.O.! Let's Be Heroes & Zootopia - Rated: T - English - Chapters: 1 - Words: 642 - Published: 3/2/2021 - K.O., Judy H., Nick W., Professor Venomous/Shadowy Figure
Ultra Adventures in Alola by Latias425 reviews
On a slow, boring day at the plaza, the bodega trio meets a professor from a region filled with fantastical creatures and are given an offer for a new and exciting adventure. Join K.O., Rad, and Enid as they explore the Alola region, meeting and befriending various Pokémon and overcoming the challenges of their island trials, even with Team Skull and Boxmore getting in the way.
Crossover - Pokémon & OK K.O.! Let's Be Heroes - Rated: K+ - English - Adventure/Friendship - Chapters: 2 - Words: 8,739 - Reviews: 6 - Favs: 2 - Follows: 3 - Updated: 3/1/2021 - Published: 4/1/2020 - Lillie, Rad, Enid, K.O.
Distorted Mirror by SneaselXRiolu
Damian is pressured to go to therapy. However, he's given the choice of choosing whoever he wants. He decides to go with a man by the name of Kaio Kincaid, who seems to have had the exact same problems that he deals with. (Discord roleplay story, cowritten by Masqueradenoir on Archive of Our Own)
Crossover - Batman & OK K.O.! Let's Be Heroes - Rated: K+ - English - Angst/Hurt/Comfort - Chapters: 1 - Words: 670 - Favs: 1 - Follows: 1 - Published: 1/17/2021 - Damian W./Robin, K.O. - Complete
The Rebellious Hero by Kombatant and Smasher
What if Laserblast didn't escape from that fateful incident at the donut shop? Follow him as he ends up in the Metaverse and he'll have to adapt to a new lifestyle once he encounters the Phantom Thieves! His heroism will be put to the test in this crossover!
Crossover - Persona Series & OK K.O.! Let's Be Heroes - Rated: T - English - Supernatural/Adventure - Chapters: 1 - Words: 18,031 - Favs: 5 - Follows: 3 - Published: 11/25/2020 - Complete
OK KO Let's Work Together by andrew.matlack reviews
First Cartoon X-Over Crossover Story! 17-year-old Bart Simpson and his friends ends up in Lakewood Turbo Plaza after having the bus broken down so they turn over to Lakewood Turbo Plaza for help as they get to see as they might had to work hard as they get to see as they get to do so. Special Appearances by Tom And Jerry!
Crossover - Cartoon X-overs & OK K.O.! Let's Be Heroes - Rated: K+ - English - Humor/Adventure - Chapters: 7 - Words: 10,377 - Reviews: 1 - Favs: 4 - Follows: 2 - Updated: 11/19/2020 - Published: 7/31/2020 - Complete
Scooby meets okko by Angry9guy reviews
when the grimwood girls invite shaggy Scooby and the gang to meet Enid trouble comes
Crossover - Scooby Doo & OK K.O.! Let's Be Heroes - Rated: K+ - English - Friendship/Mystery - Chapters: 1 - Words: 34 - Reviews: 1 - Favs: 1 - Follows: 1 - Published: 6/15/2020 - Scooby Doo, Grimwood Girls, Enid, K.O.
Let's (Not) Be Smashers by Latias425 reviews
On a normal day in Lakewood Plaza Turbo, K.O. finds a strange letter which is an invitation for him to come to a fighting tournament called Super Smash Bros. Upon arriving at the Smash Mansion however, things start to get really crazy as when Master Hand finds out who has come to the tournament, he forms an ensemble to try to get K.O. out since cartoon characters can't be in Smash.
Crossover - Super Smash Brothers & OK K.O.! Let's Be Heroes - Rated: T - English - Adventure/Parody - Chapters: 24 - Words: 46,079 - Reviews: 11 - Favs: 23 - Follows: 19 - Updated: 5/28/2020 - Published: 5/22/2018 - Samus A., K.O., Carol, TKO
Team up Dueling by Determined Artist reviews
Astral floated around following Yuma with Kotori and Bronk followed be hind them, during Duel recess. The group soon find a pair of twins that need help.
Crossover - Yu-Gi-Oh! ZEXAL & OK K.O.! Let's Be Heroes - Rated: K+ - English - Friendship - Chapters: 1 - Words: 1,092 - Reviews: 1 - Favs: 5 - Follows: 4 - Published: 5/6/2020 - Yuma T., Astral, K.O., TKO - Complete
The Origin of WordGirl! by ImGonnaWriteAFanfic
This is how WordGirl was started!
Crossover - WordGirl & OK K.O.! Let's Be Heroes - Rated: K - English - Adventure - Chapters: 1 - Words: 132 - Favs: 1 - Follows: 1 - Published: 3/3/2020 - WordGirl/Becky B., Lord Boxman - Complete
OK Steven Lets Be Heroes! by IamPancakeSatan666 reviews
Steven Universe meets KO, a kid who just so happens to know Garnet! Meanwhile, Lord Boxman is cooking up a plan to get rid of KO, but will Steven protect KO?
Crossover - Steven Universe & OK K.O.! Let's Be Heroes - Rated: T - English - Humor/Adventure - Chapters: 1 - Words: 196 - Reviews: 1 - Favs: 7 - Follows: 6 - Published: 3/2/2020 - Steven U., K.O.
Unikitty's Love Story! by ImGonnaWriteAFanfic reviews
Unikitty is in love with Enid but how can she show it?
Crossover - OK K.O.! Let's Be Heroes & Unikitty! - Rated: K - English - Romance - Chapters: 1 - Words: 128 - Reviews: 2 - Published: 2/5/2020 - Enid, Unikitty - Complete
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