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The Amazing SnowSpider by Nightwing Josh
Spin off of "Four Peters Vs. The Sinister Six." It's been a few months since Peter-3 went to Earth-199999. He meets and befriends a doppelgänger of Caitlin Snow from another universe. Together, they must deal with Harry Osborn, seeking revenge and avoid being successfully hunted by Kraven.
Crossover - Spider-Man & Flash - Rated: T - English - Adventure/Romance - Chapters: 2 - Words: 11,915 - Favs: 7 - Follows: 6 - Updated: 4/25 - Published: 4/25/2024 - [Peter P./Spider-Man, Dr. Caitlin S.] Harry O., Kraven
Champions & Wars by Aragorn II Elessar reviews
Earth-199999 is faced with strife from within. Lucifer of Earth-205 escapes. Sora, Donald and Goofy continue to run through Middle-earth to help the Fellowship. Some Jedi and a certain Sith have a vision. In the meantime, all the worlds continue to battle threats from other worlds. The Multiverse is still a mess. Sequel to 'Heroes coming together'. Part 2 of 'When Legends meet'.
Crossover - Flash & Avengers - Rated: M - English - Adventure/Supernatural - Chapters: 8 - Words: 213,788 - Reviews: 121 - Favs: 66 - Follows: 53 - Updated: 4/25 - Published: 1/24 - Barry A./The Flash, Cisco R., Captain America/Steve R., Thor
Sages Of Speed by Hector Flores reviews
What happens when Chakra and other forces is introduced into the Flash 2014 why chaos balance and a lot of shenanigans come along and see what happens with Barry and Eddy and the Flash team on this wild ride. this is an AU harem story
Crossover - Flash & Naruto - Rated: M - English - Romance/Adventure - Chapters: 1 - Words: 6,181 - Reviews: 2 - Favs: 11 - Follows: 11 - Published: 4/23
Flashpoint Mayhem by TrueHorror88 reviews
Another victory for the team, yet someone was unable to celebrate that and chose to make a world-shaking decision. Barry saved his mother from death, changing his past and his present, but it also affected others without him knowing. Seth and his family are just as affected, maybe more. The team faces newer threats, but they're not new to the Lethal Protector. They're threats.
Crossover - Flash & Venom - Rated: M - English - Adventure/Romance - Chapters: 25 - Words: 838,426 - Reviews: 130 - Favs: 167 - Follows: 178 - Updated: 4/20 - Published: 4/18/2021 - [Dr. Caitlin S., OC] Killer Frost
Heroes, villains and Slayers by Stand with Ward and Queen reviews
The spell to activate every Slayer affected more than just one world. It affected the entire multiverse. Now, the Scoobies are forced to travel to different earths and try to undo the damage that has been done, even as people on these earths attempt to take advantage of this opportunity.
Crossover - Buffy: The Vampire Slayer & Flash - Rated: T - English - Supernatural/Adventure - Chapters: 5 - Words: 35,110 - Reviews: 19 - Favs: 23 - Follows: 19 - Updated: 4/17 - Published: 2/12 - Buffy S., Willow R., Barry A./The Flash, Oliver Q./The Arrow
Agent S : No Way Home (BRANCH of Agent S) by What If Universe reviews
In one universe, Peter Parker-Coulson managed to stop Mysterio and was dragged into a Crisis. But in this universe, Peter's identity was revealed, sending everything into a spiral as his team was dragged down with him. Peter goes to Dr. Strange for help, thinking that he found a way to fix things. But things quickly got out of hand when they tampered with the multiverse.
Crossover - Spider-Man & Flash - Rated: T - English - Parody/Family - Chapters: 18 - Words: 45,138 - Reviews: 40 - Favs: 42 - Follows: 39 - Updated: 4/17 - Published: 8/22/2022 - Peter P./Spider-Man, Eobard T./Impostor Harrison W./Reverse-Flash, Savitar, Nora W.A./XS - Complete
KARRY- SUPERFLASH ONE SHOTS by KingMaster2526
ONE SHOTS SUPERFLASH / KARRY
Crossover - Flash & Supergirl - Rated: K+ - Spanish - Romance/Family - Chapters: 7 - Words: 20,404 - Favs: 2 - Follows: 2 - Updated: 4/12 - Published: 1/8/2023 - Barry A./The Flash, Cisco R., Kara D./Supergirl, Alex D.
Avenging Flash: Age Of Ultron (Book Two) by G4dgetJunior reviews
In Book Two of this series, Barry Allen and the Avengers must face off against the next major foe to threaten the earth. A corrupted and homicidal AI, hell bent on humanities extinction. It's name? Ultron. (NO COMMISSION ARTISTS PLEASE!)
Crossover - Flash & Avengers - Rated: T - English - Sci-Fi/Adventure - Chapters: 12 - Words: 28,784 - Reviews: 34 - Favs: 24 - Follows: 29 - Updated: 4/11 - Published: 2/16/2024 - Barry A./The Flash, Pietro M./Quicksilver, Ultron, Wanda M./Scarlet Witch - Complete
Maybe It Was Destiny by 2PNUG
This is an alternate ending of The Flash 6x16 with some Superflash. (This has spoilers from seasons 6 and 5 of The Flash and Supergirl.) I don't own any of the characters.
Crossover - Flash & Supergirl - Rated: T - English - Romance/Hurt/Comfort - Chapters: 3 - Words: 11,163 - Favs: 3 - Follows: 4 - Published: 4/8 - [Barry A./The Flash, Kara D./Supergirl] Cisco R., Alex D.
When Hope and Love mix by 2PNUG reviews
After reflecting on the past year. Barry is told his death is the key to the multiverse survival. But will a certain Kryptonian accept that? Starts between episodes 6:08 and 6:09 of the flash, and episodes 5:08 and 5:09 of Supergirl. Continues post Crisis
Crossover - Flash & Supergirl - Rated: T - English - Romance/Hurt/Comfort - Chapters: 29 - Words: 88,231 - Reviews: 6 - Favs: 9 - Follows: 10 - Updated: 4/8 - Published: 3/11 - [Barry A./The Flash, Kara D./Supergirl] Oliver Q./The Arrow, Alex D.
Love My Superfriend by 2PNUG
As Kara attends Alex & Kelly's wedding, a certain scarlet speedster shows up fashionably late, and the two share a heartfelt encounter about life, mistakes, and their future.
Crossover - Flash & Supergirl - Rated: T - English - Romance/Drama - Chapters: 7 - Words: 16,509 - Favs: 5 - Follows: 5 - Updated: 4/7 - Published: 3/25 - [Barry A./The Flash, Kara D./Supergirl] Dr. Caitlin S., Alex D.
Justice League Chronicles Book 2: Inductions by Lauriverfanboy1 reviews
The Justice League inducts it's new members. This story is a series of one-shots and won't be updated as regularly as the others.
Crossover - Flash & Supergirl - Rated: T - English - Chapters: 2 - Words: 2,145 - Reviews: 6 - Favs: 9 - Follows: 8 - Updated: 4/6 - Published: 1/11 - Barry A./The Flash, Dr. Caitlin S., Oliver Q./The Arrow, Kara D./Supergirl
Justice League Chronicles Book 3: Fort Rozz by Lauriverfanboy1 reviews
To deal with the threat of Red Daughter using the Phantom Zone projector to release her father from the Zone, Supergirl rallies the entire Justice League to help her attack Fort Rozz. Part 7 of New World Chronicles.
Crossover - Flash & Supergirl - Rated: T - English - Chapters: 9 - Words: 7,840 - Reviews: 9 - Favs: 10 - Follows: 8 - Updated: 4/5 - Published: 3/25 - Kara D./Supergirl, Clark K./Superman, Bruce W./Batman - Complete
The Crimson Speedster by choejhulkp9 reviews
Barry Allen AKA the Flash wasn't the only one who was affected by the particle accelerator. He and Star Labs find another speedster who has similar powers to Barry, yet he's a bit different. Watch as the Scarlet Speedster joins the Crimson Speedster possibly join forces and protect Central City. Naruto x Linda x ?
Crossover - Flash & Naruto - Rated: M - English - Chapters: 23 - Words: 725,080 - Reviews: 898 - Favs: 2,233 - Follows: 2,252 - Updated: 4/4 - Published: 12/18/2015 - Linda P., Naruto U.
The Reboot by ki58ran reviews
A "Crisis on Infinite Earths" Aftermath Story. SnowBarry/SuperFlash
Crossover - Flash & Supergirl - Rated: T - English - Drama/Suspense - Chapters: 47 - Words: 93,013 - Reviews: 96 - Favs: 97 - Follows: 104 - Updated: 4/1 - Published: 6/8/2020 - [Barry A./The Flash, Dr. Caitlin S.] Jesse Q., Kara D./Supergirl
Karry Universe by CharmedMilliE- Karry Master reviews
In an alternate universe both Barry and Kara exist together. This is what happens when they meet in college and fall in love. Follow them, their family, and friends through life from college years to being superheroes and beyond. This is Karry Universe. Leading the Millma Verse.
Crossover - Flash & Supergirl - Rated: T - English - Romance - Chapters: 214 - Words: 1,219,481 - Reviews: 3541 - Favs: 1,747 - Follows: 1,516 - Updated: 3/29 - Published: 3/4/2016 - [Barry A./The Flash, Kara D./Supergirl]
Hidden Past by Roswelllostcause reviews
When Caitlin Snow was 13 she was bitten by a werewolf while visiting her Aunt and younger cousin in Beacon Hills.
Crossover - Flash & Teen Wolf - Rated: T - English - Supernatural - Chapters: 12 - Words: 17,830 - Reviews: 5 - Favs: 13 - Follows: 12 - Updated: 3/20 - Published: 12/6/2024 - Barry A./The Flash, Dr. Caitlin S., Scott M., Derek H.
The Speedster and The Spider by Nightwing Josh reviews
Sequel/Spinoff of "Four Peters Vs. The Sinister Six." After his ordeal on Earth-199999, Peter-4 finds that things are not what they seem. Caitlin and Frost aren't married to him, but dating other men and Barry is married to Iris again. AU of Flash S8 & 9. Not for fans of WestAllen and Mark Blaine. Warning: Some strong language and sensitive topics brought up
Crossover - Spider-Man & Flash - Rated: T - English - Drama/Hurt/Comfort - Chapters: 15 - Words: 123,271 - Reviews: 30 - Favs: 19 - Follows: 25 - Updated: 3/17 - Published: 4/25/2024 - [Peter P./Spider-Man, Killer Frost, Dr. Caitlin S.] Barry A./The Flash
A Web of Problems (BRANCH of Book 2) by What If Universe reviews
Peter Parker and Natalia Rushman live a relatively normal life. Well, as normal as it can be when you're in love with Spider-Man, who has been protecting Central City for years. But everything changes when the particle accelerator explodes, and Natalia starts having visions of another life she can't recall. Who is she? Why do these visions feel too real to be dreams?
Crossover - Marvel & Flash - Rated: T - English - Mystery/Family - Chapters: 8 - Words: 27,270 - Reviews: 12 - Favs: 28 - Follows: 35 - Updated: 3/12 - Published: 12/30/2024 - [P. Parker/Spider-Man, N. Romanov/Black Widow] [Dr. Caitlin S., Ronnie R./One-half of Firestorm]
A far way from home (BRANCH of Book 2) by What If Universe reviews
Peter Allen, the son of Earth-90's Barry Allen, has been saving people as Spider-Man for the past ten years, taking over after his father's retirement as the Flash. When his enemies create a vortex that sends them to an unfamiliar world that feels similar but is entirely different, Peter must adapt and find a way back. Will he succeed or will this strange world become his new home?
Crossover - Spider-Man & Flash - Rated: T - English - Adventure/Fantasy - Chapters: 3 - Words: 17,502 - Reviews: 5 - Favs: 19 - Follows: 21 - Updated: 3/12 - Published: 2/17 - Peter P./Spider-Man, Barry A./The Flash, Dr. Caitlin S., Patty S.
The PJ masks meet The Flash by PJ Masks 2023 reviews
In a town called Tarabiscoville, a boy named Connor gets hit by particle excelerator and becomes none other than… Catboy. but his journey had just begun. due to the death of his sister Wendy, who was killed by none other than the reverse Cameron. Connor would have to leave his life and live in Central city. Where he will meet another speedster named The Flash. AKA Barry Allen.
Crossover - PJ Masks & Flash - Rated: K - English - Adventure - Chapters: 16 - Words: 24,497 - Reviews: 3 - Favs: 1 - Follows: 2 - Updated: 3/8 - Published: 8/18/2022 - Barry A./The Flash
Total War: The Flash by Dark Days Dune reviews
Part 1 of the Total War series. Barry Allen's life as the Flash has only been underway to his third year and has been more difficult with the effects of Flashpoint. However, Barry must put away his personal issues as a multiverse war finds its way to Earth 1, forcing him to jump into action with a sea of foes and allies both new and alike.
Crossover - Flash & Arrow - Rated: M - English - Sci-Fi/Angst - Chapters: 11 - Words: 49,725 - Reviews: 33 - Favs: 13 - Follows: 14 - Updated: 3/4 - Published: 3/30/2024 - Barry A./The Flash, Cisco R., Oliver Q./The Arrow, John D./Spartan
Lightning Effect by Khristeena Vance reviews
Harry Potter and Diamond Black are two best friends trying to raise a child in a world that no longer cares to protect itself. It only makes sense that they'd leave the world, doesn't it? Central City is different. Central City is their home. One they must protect.
Crossover - Harry Potter & Flash - Rated: T - English - Fantasy - Chapters: 1 - Words: 1,328 - Reviews: 3 - Favs: 6 - Follows: 12 - Published: 3/2 - Harry P., OC, Teddy L.
Future Foundation 2 : Family Matters by What If Universe reviews
It's been 2 years since the singularity and things are going well for Peter and his team. Everyone is happy and content but little did Peter know that it was only the beginning of something much larger. Peter and his team will now have to defend the world and even the universe from threats even more powerful than before because if they fail everything they love will be destroyed.
Crossover - Flash & Fantastic Four - Rated: T - English - Sci-Fi/Suspense - Chapters: 10 - Words: 80,814 - Reviews: 34 - Favs: 40 - Follows: 44 - Updated: 2/28 - Published: 3/5/2024 - [Spider-Man/Peter P., Invisible Woman/Susan S.] Jay G./The Flash, Dr. Doom/Victor V.
Omber by Crimson Lotus Demon reviews
After the end of the 4th Shinobi World War, Naruto lived and died surrounded by his many grandchildren. However, in a turn of "fate", Naruto was given a second chance at a better life. Reborn on October 10, 1987 as Nathen Jay Allen in Central City, Nathen and his younger brother Barry, must traverse the new world of metahumans together.
Crossover - Flash & Naruto - Rated: M - English - Sci-Fi/Adventure - Chapters: 3 - Words: 21,794 - Reviews: 75 - Favs: 507 - Follows: 562 - Updated: 2/19 - Published: 6/9/2020 - [Dr. Caitlin S., Naruto U.] [Barry A./The Flash, Patty S.]
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