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Batman and the Masquerade of Hastur Part 1 by Darkspawndweller04 reviews
When Batman and Alfred get invited to a strange party they find that they are not the only ones who have been pulled from their daily lives. Many characters from different worlds and walks of life and brought together. How will they deal with the mind games of Hastur? Warning: contains poop, Thanos dressed as some sort of Pharoah and sad Voldemort.
Crossover - Batman & Cthulhu Mythos - Rated: M - English - Supernatural/Horror - Chapters: 1 - Words: 3,630 - Reviews: 1 - Published: 11/18 - Alfred P., Bruce W./Batman, Harvey D. - Complete
RWBY Noir by Wombag1786 reviews
"The most merciful thing in the world, I think, is the inability of the human mind to correlate all its content." In 1919, the world has seen the horrors of the great war come to an end, yet forces behind the vale of sanity work and worm into the booming new world. Thankfully, humanity will not be alone in this madness. Though Madness, may prove to be a Blessing then Sanity.
Crossover - Cthulhu Mythos & RWBY - Rated: M - English - Mystery/Horror - Chapters: 50 - Words: 398,923 - Reviews: 188 - Favs: 101 - Follows: 112 - Updated: 11/14 - Published: 10/16/2019 - OC, Team RWBY, Team RNJR
Universo Lovecraft-Park by ReyNoMuerto
Cthulhu había sido derrotado, Mint-Berry Crunch le había robado a Kenny su oportunidad de entender quién o qué era realmente; pero eso no significaba que fuera a rendirse tan fácilmente. Estaba decidido a seguir investigando sobre el Necronomicón , sobre los Antiguos y sobre su maldición. Seguiría la huella de los dioses hasta donde fuera que esta lo condujera, hasta el final.
Crossover - South Park & Cthulhu Mythos - Rated: M - Spanish - Adventure/Supernatural - Chapters: 16 - Words: 47,331 - Updated: 11/9 - Published: 10/1 - Eric Cartman, Kenny M., Kyle B., Stan M.
Le rêveur by AvaTarbleu reviews
D'abord un arbre, ensuite un lac, les scènes s'enchaînent et Loki fait de mauvais rêves.
Crossover - Prisoners & Cthulhu Mythos - Rated: T - French - Crime - Chapters: 20 - Words: 15,864 - Reviews: 40 - Favs: 1 - Follows: 2 - Updated: 11/7 - Published: 1/10/2021 - D. Loki
Child of the Crawling Chaos by Alias001 reviews
No true summary yet. Eldritch stuff. Fem(?)Harry.
Crossover - Harry Potter & Cthulhu Mythos - Rated: M - English - Adventure/Supernatural - Chapters: 9 - Words: 4,555 - Reviews: 19 - Favs: 132 - Follows: 181 - Updated: 10/28 - Published: 5/4 - Harry P.
The Bored Outer God II: Through the Gate by Daemon-Sultan reviews
In 2081, a gate mysteriously opens in Santa Maria, a city in the Antarctic Dominion's Province of Naashoth. Out of it comes an opportunity, a casus beli, a chance for the great Antarctian war machine to move once again.
Crossover - Cthulhu Mythos & Gate - Jietai Kare no Chi nite, Kaku Tatakeri - Rated: M - English - Horror/Humor - Chapters: 5 - Words: 37,139 - Reviews: 4 - Favs: 36 - Follows: 41 - Updated: 10/11 - Published: 10/18/2021 - Pina
Beyond Angled Space by Qoheleth reviews
In which it is revealed where Uncle Andrew's dust came from, what the compiler of the Commoriom myth-cycle did in his dreams, and how Discord first came to Equestria. (Yes, it's actually one of those triple crossovers they don't let you label.)
Crossover - Chronicles of Narnia & Cthulhu Mythos - Rated: K+ - English - Supernatural - Chapters: 1 - Words: 3,904 - Reviews: 3 - Favs: 1 - Published: 9/24 - Complete
Yog-Sothoth by Sophie Gamer Girl 7z reviews
Se avecina una nueva guerra santa, en un universo distinto, en un sitio muy alejado de las fronteras mágicas de los héroes que conocemos, y de este modo, está guerra santa presenta a un nuevo guerrero. Por que Yog-Sothoth el supremo dios del conocimiento ha decidido usar este conflicto para luchar contra Nyarlathothep. (Precuela de Yog-Sothoth grand order)
Crossover - Fate/stay night & Cthulhu Mythos - Rated: T - Spanish - Horror/Adventure - Chapters: 1 - Words: 1,347 - Reviews: 2 - Published: 9/12 - Complete
Eldritch Dragon Slayer by Hakimaster38 reviews
The multiverse is an interesting place, one of infinite possibilities. One of these possibilities became reality when a young dragon slayer discovers a tome of forbidden knowledge that sends the world of earthland on a downward spiral through the realms of depravity, anguish and insanity that is beyond mortal understanding.
Crossover - Cthulhu Mythos & Fairy Tail - Rated: M - English - Horror/Sci-Fi - Chapters: 12 - Words: 59,693 - Reviews: 7 - Favs: 28 - Follows: 24 - Updated: 9/5 - Published: 4/7 - Wendy M., Carla
Fate Extra : The Music of the Spheres by celian Cogitore reviews
And in its dark ages, even death can die... 2099, a tragic time, a world ravaged by war and where corruption reigns. As the end of the world seems imminent, a hibernation capsule containing the last Master reappears. With the awakening of Hakuno Kishinami a new Grail War begins!
Crossover - Fate/stay night & Cthulhu Mythos - Rated: M - English - Supernatural/Sci-Fi - Chapters: 41 - Words: 191,992 - Reviews: 75 - Favs: 103 - Follows: 117 - Updated: 8/22 - Published: 1/23/2020 - [Hakuno K., Tamamo] Gilles de Rais/Bluebeard, Jeanne d'Arc - Complete
A Snake Called Nyarlathotep by Daemon-Sultan reviews
In London, four very different people team up on a jewel heist, then try to double-cross one another for the loot- wait, wrong, uh, everything. When High-Pharaoh Nyaralthotep is summoned by a cult to do their dirty work, he finds himself thrust into a universe where Dumbledore is an evil idiot, the Weasleys are scheming, Harry Potter is female, and Hermione is a terrible person.
Crossover - Harry Potter & Cthulhu Mythos - Rated: M - English - Parody/Humor - Chapters: 4 - Words: 35,056 - Reviews: 2 - Favs: 50 - Follows: 73 - Updated: 8/8 - Published: 3/2 - [Harry P., Draco M.] George W., Fred W.
What Rests Above, Rest Below by Zeroraid reviews
He wasn't supposed to be here, not in this world - this shard of reality. But here he was, a Seeker upon a world abandoned by its own Gods and now held by Ones left unseen. Remnant has him now, and he knows how it's story is "supposed" to play out. That doesn't mean its going to. The Old Ones has changed the script, and the Seeker has his own little edits to make to it. Revision
Crossover - Cthulhu Mythos & RWBY - Rated: M - English - Supernatural/Sci-Fi - Chapters: 3 - Words: 8,600 - Reviews: 1 - Favs: 9 - Follows: 14 - Updated: 7/13 - Published: 3/21 - OC
Mythos Effect by Omniscent1 reviews
A crossover between Mass Effect and Cthulhutech. Humanity has won the Aeon War and has since expanded and thrived. How will the galaxy fare with this new power?
Crossover - Cthulhu Mythos & Mass Effect - Rated: M - English - Sci-Fi/Adventure - Chapters: 25 - Words: 192,840 - Reviews: 1672 - Favs: 4,591 - Follows: 5,316 - Updated: 7/9 - Published: 6/5/2013 - Saren A., Shepard, OC
One-Shots and Misc by Daemon-Sultan
Just miscellaneous ideas, one-shots, multiple-shots, whatever-shots.
Crossover - Harry Potter & Cthulhu Mythos - Rated: M - English - Humor/Parody - Chapters: 1 - Words: 217 - Favs: 1 - Follows: 1 - Published: 6/24
The Great Old Ones by Fire Slash reviews
(AU!). Their kind have existed long before humans. They are responsible for many unexplained phenomena, such as the development of quirks. They have created so much, yet when they rise, they WILL be the end of humanity. The only hope of stopping them resides in a strange young boy. He is an anomaly; a being of both worlds…
Crossover - Cthulhu Mythos & My Hero Academia/僕のヒーローアカデミア - Rated: T - English - Horror/Supernatural - Chapters: 2 - Words: 11,215 - Reviews: 27 - Favs: 229 - Follows: 278 - Updated: 6/17 - Published: 7/2/2021 - Izuku M., Daruma U., Moonfish, Kurogiri
Harry Potter y el libro de los Antiguos by ReyNoMuerto
La vida del pequeño Harry siempre estuvo atormentada por las pesadillas. En ellas veía una biblioteca prohibida de conocimientos arcanos. Con el paso del tiempo, los secretos de saberes más allá de la comprensión del hombre se revelaron a él a través de un libro maldito. El destino de Harry era uno más grande y terrible de lo que cualquier ser pudo haber imaginado.
Crossover - Harry Potter & Cthulhu Mythos - Rated: T - Spanish - Horror/Fantasy - Chapters: 1 - Words: 4,509 - Favs: 8 - Follows: 6 - Published: 6/15 - Harry P. - Complete
Weak Man's Apotheosis by Isbrandir Blake reviews
The crawling caos, Nyarlathotep, is no stranger to family and love ( love is more real than most laws of reality anyway ). But after an unprecedented event his family life will change a lot. For Izuku is the best thing that could have happened. # Azathoth best grandpa
Crossover - Cthulhu Mythos & My Hero Academia/僕のヒーローアカデミア - Rated: K+ - English - Supernatural/Family - Chapters: 33 - Words: 28,438 - Reviews: 6 - Favs: 46 - Follows: 50 - Updated: 6/6 - Published: 2/28 - Izuku M., Inko M., Hisashi M.
Shadows Over Fuuka by DrummondType2 reviews
Mai-HiME reimagined as a part of the Cthulhu Mythos.
Crossover - Mai HiME & Cthulhu Mythos - Rated: T - English - Horror/Supernatural - Chapters: 6 - Words: 12,753 - Reviews: 1 - Favs: 3 - Follows: 3 - Updated: 5/25 - Published: 5/13 - [Natsuki K., Shizuru F.] Mai T., Mikoto M.
Stories, Rewritten by DarkEmpress239
A rewrite of an earlier work on Ao3 that I orphaned. It's a story a chapter. Fandoms tagged aren't the only fandoms, hence the fandom being in the chapter title (FFN sucks in the multifandom department). The inspiration is at the top of the chapter, and explanation at the bottom.
Crossover - Harry Potter & Cthulhu Mythos - Rated: T - English - Tragedy/Horror - Chapters: 5 - Words: 1,227 - Published: 5/14 - OC
Jaune'Arc - Hafh'drn ot N'gha Tharanak by Gavenga323 reviews
It wasn't supposed to be here. But it was here, inside his head. It always had been. Now Jaune has to go around the world hunting that which only he understands. But it could be worse, at least he didn't have to wait for the stars to align. 'Ain't that right, Nyarlathotep' 'You gave yourself this job, boy, don't look at me in that tone of voice.' M for violence, language & CTHULHU!
Crossover - Cthulhu Mythos & RWBY - Rated: M - English - Humor/Adventure - Chapters: 6 - Words: 75,969 - Reviews: 133 - Favs: 593 - Follows: 720 - Updated: 5/1 - Published: 7/8/2020 - Jaune A.
Paranoid Ramblings by Entropy Vex reviews
Just the half mad rambling of a paranoid insomniac and other miscellaneous things. (Initial chapter is a repost)
Crossover - X-overs & Cthulhu Mythos - Rated: T - English - Supernatural/Horror - Chapters: 1 - Words: 155 - Reviews: 1 - Favs: 1 - Follows: 1 - Published: 4/5
Seekers of Remnant by Zeroraid reviews
He wasn't supposed to be here, not in this world - this shard of reality. But here he was, a Seeker upon a world abandoned by its own Gods and now held by One best unseen. Remnant has him now, and he knows how it's story is "supposed" to play out. That doesn't mean its going to. The Old One has changed the script, and the Seeker has his own little edits to make to it.
Crossover - Cthulhu Mythos & RWBY - Rated: M - English - Horror/Adventure - Chapters: 6 - Words: 16,040 - Reviews: 8 - Favs: 52 - Follows: 69 - Updated: 3/15 - Published: 10/17/2021 - OC, Neo, Team RWBY
Xenos in Yellow by Hakimaster38 reviews
After a cataclysmic battle with his half brother, and a 10 million year nap the King in Yellow awakens to find a world where god's walk among mortals. What is a shepherd to do when they've lost their sheep, but find them and where better than the dungeon. It's his castle after all.
Crossover - Dungeon ni Deai o Motomeru no wa Machigatte Iru Darou ka & Cthulhu Mythos - Rated: T - English - Mystery/Sci-Fi - Chapters: 6 - Words: 28,105 - Reviews: 12 - Favs: 48 - Follows: 52 - Updated: 3/3 - Published: 2/10 - Wiene, Ray, Bell C. - Complete
The Horror at Hogwarts by emscribblings reviews
In 1942, three students disappeared, their bodies never found. The handful of survivors refused to speak of what had occurred, and the truth remained buried and forgotten. In his final days, the reclusive Abraxas Malfoy wrote down the damning words of his tale. Of a time when he pursued immortality and power alongside Tom Riddle — one of the vanished.
Crossover - Harry Potter & Cthulhu Mythos - Rated: T - English - Horror/Fantasy - Chapters: 1 - Words: 15,974 - Reviews: 5 - Favs: 38 - Follows: 16 - Published: 2/4 - Tom R. Jr., Abraxas M. - Complete
Lovecraftian Error by Anonymous Wandmaker reviews
In 1993, deep in the Department of Mysteries, an experiment goes wrong & monsters gain a foothold past the barriers that separate the human world from the other realm and begin to wreck havoc subtly. In Hogwarts, 2 unassuming girls, Sally Anne & Luna start to realize something is wrong, & because of how it affects them, try to find a way to right things. PostingOnRoyalRoad.
Crossover - Harry Potter & Cthulhu Mythos - Rated: K+ - English - Mystery/Adventure - Chapters: 4 - Words: 12,866 - Reviews: 5 - Favs: 13 - Follows: 18 - Updated: 1/31 - Published: 1/18 - Sally-Anne P., Luna L., Albus D., Harry P.
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