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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: 34 - Words: 161,784 - Reviews: 64 - Favs: 83 - Follows: 100 - Updated: 2/20 - Published: 1/23/2020 - [Hakuno K., Tamamo] Gilles de Rais/Bluebeard, Jeanne d'Arc
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: 3 - Words: 13,361 - Reviews: 8 - Favs: 23 - Follows: 30 - Updated: 2/18 - Published: 2/10 - Wiene, Ray, Bell C.
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: 38 - Words: 327,840 - Reviews: 150 - Favs: 68 - Follows: 79 - Updated: 2/7 - Published: 10/16/2019 - OC, Team RWBY, Team RNJR
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: 14 - Words: 10,993 - Reviews: 27 - Favs: 1 - Follows: 2 - Updated: 2/6 - Published: 1/10/2021 - D. Loki
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: 3 - Favs: 18 - Follows: 8 - 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: 6 - Follows: 12 - Updated: 1/31 - Published: 1/18 - Sally-Anne P., Luna L., Albus D., Harry P.
NGE: Screams of Nightmares by Beastrider9 reviews
There are things out there far worse than the Angels. One of them has taken notice of the Events of Tokyo-3 and has machinations and plans of his own. He is Nyarlathotep, the Crawling Chaos.
Crossover - Evangelion & Cthulhu Mythos - Rated: T - English - Horror/Sci-Fi - Chapters: 18 - Words: 94,971 - Reviews: 244 - Favs: 261 - Follows: 274 - Updated: 1/25 - Published: 11/24/2019
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: 3 - Words: 23,820 - Reviews: 3 - Favs: 24 - Follows: 29 - Updated: 1/15 - Published: 10/18/2021 - Pina
Hostis Publicus by Daemon-Sultan
In 1871, a man known only as Rattlesnake began a reign of terror across the American West. Over a decade later he would be known by many more names, the King of Thieves, the Prince of Murderers, the Red Reaper, and in more scholarly circles, Hostis Publicus or public enemy. AN: This is a spinoff of the Bored Outer God series.
Crossover - Cthulhu Mythos & Harry Potter - Rated: M - English - Western/Humor - Chapters: 1 - Words: 5,340 - Favs: 1 - Follows: 1 - Published: 12/25/2021
Of Mythos and Monsters by Mah Lawn reviews
What happens when intentional grimdark crosses with accidental grimdark? This story tries to answer that, in which a ship full of Elder Things encounters a planet full of Monster Girls, and everything will likely go wrong for everyone involved.
Crossover - Cthulhu Mythos & Monster Girl Encyclopedia - Rated: T - English - Adventure/Humor - Chapters: 2 - Words: 8,838 - Reviews: 3 - Favs: 17 - Follows: 24 - Updated: 12/18/2021 - Published: 9/8/2021
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: 5 - Words: 14,145 - Reviews: 6 - Favs: 32 - Follows: 45 - Updated: 12/10/2021 - Published: 10/17/2021 - OC, Neo, Team RWBY
Cthulhu VI by Dr. Gairyuki
It's Halloween now on the Boiling Isle. Something was about to be unleashed on the unsuspecting residents and the Boiling Isle itself...
Crossover - Owl House & Cthulhu Mythos - Rated: K+ - English - Humor/Horror - Chapters: 2 - Words: 10,110 - Favs: 4 - Follows: 1 - Updated: 10/31/2021 - Published: 10/22/2021 - [Luz N., Amity B.] Hooty - Complete
Harry Potter and the Bored Outer God by Daemon-Sultan reviews
In which Harry Potter is an avatar of Nyarlathotep. Post-GOF
Crossover - Harry Potter & Cthulhu Mythos - Rated: M - English - Horror/Humor - Chapters: 13 - Words: 60,527 - Reviews: 21 - Favs: 129 - Follows: 136 - Updated: 10/18/2021 - Published: 10/21/2020 - Harry P., Hermione G. - Complete
Maddening Bell by Touhoufanatic reviews
Leaving his village to head to Orario to become a Hero, Bell Cranel witnesses a falling star and goes to investigate only to meet a Goddess quiet unlike any he, or anyone, has ever seen. his fate is now changed, for he has piqued the interest of none other than the Crawling Chaos, of Nyarlathotep, and nothing will be as fate had planned.
Crossover - Cthulhu Mythos & Dungeon ni Deai o Motomeru no wa Machigatte Iru Darou ka - Rated: M - English - Fantasy/Horror - Chapters: 6 - Words: 38,011 - Reviews: 37 - Favs: 285 - Follows: 366 - Updated: 10/15/2021 - Published: 5/11/2021 - Bell C.
XCOM: Mythos Point by Zeroraid reviews
The Ethereal War ended a long time ago, and Humanity took topreparing for the Ethereal's return. Unfortunately as they prepared for one enemy, a second crept out the shadows of the ocean and the cities they defended. It is the years 2177, and the New Earth Government keeps a tight grasp on world after the open warfare between XCOM, sea monster and cultist have taken to the shadows.
Crossover - X-Com & Cthulhu Mythos - Rated: T - English - Sci-Fi/Supernatural - Chapters: 8 - Words: 27,259 - Reviews: 8 - Favs: 10 - Follows: 12 - Updated: 9/25/2021 - Published: 12/24/2020 - OC
The Gods Awaken by RobbyA reviews
Nyarlathotep returns to the Boiling Isles to bring chaos to it.
Crossover - Cthulhu Mythos & Owl House - Rated: T - English - Adventure - Chapters: 30 - Words: 70,742 - Reviews: 26 - Favs: 22 - Follows: 24 - Updated: 9/9/2021 - Published: 12/18/2020
In fire by jajafilm
This is a crossover of the TV series Supernatural and the work of H. P. Lovecraft. Burning books is an instrument of oppression and propaganda; it is also a sign of barbarism and an attempt to prevent people from accessing information. But what if a book is burned that should never have been written?
Crossover - Supernatural & Cthulhu Mythos - Rated: K - English - Supernatural/Fantasy - Chapters: 1 - Words: 238 - Favs: 2 - Follows: 2 - Published: 8/28/2021 - Sam W., Castiel - Complete
The Eldritch Empire by scifienthusiast reviews
(This is the rewrite of Migou Queen of Earth Bet story.) A cosmic horror thinks that an altered human teenager can remove a pest problem for his kind. Mankind is never the same again.
Crossover - Cthulhu Mythos & Worm - Rated: T - English - Sci-Fi/Supernatural - Chapters: 1 - Words: 6,106 - Reviews: 5 - Favs: 80 - Follows: 98 - Published: 8/21/2021 - Skitter
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: 23 - Words: 172,566 - Reviews: 1500 - Favs: 4,181 - Follows: 4,853 - Updated: 8/15/2021 - Published: 6/5/2013 - Saren A., Shepard, OC
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: 1 - Words: 8,144 - Reviews: 14 - Favs: 148 - Follows: 179 - Published: 7/2/2021 - Izuku M., Daruma U., Moonfish, Kurogiri
Proper Care Of A Stray by Jaycren reviews
They Say That Curiosity Killed The Cat But Satisfaction Brought Her Back. Who Is This Cute Boy, So Intent On Walking Toralei To School? ToraleixOC, Minor Lovecraftian influences. Fluffiness incoming.
Crossover - Cthulhu Mythos & Monster High - Rated: T - English - Romance/Friendship - Chapters: 8 - Words: 8,792 - Reviews: 4 - Favs: 14 - Follows: 14 - Updated: 6/15/2021 - Published: 6/15/2018 - Toralei, OC
Lovecraft's Curse on this Third-Rate World by Jackie Avocado reviews
The Outer Gods have granted me a Gamer System unlike anything the internet has ever seen! All the while they watch my progress like some kind of Twitch stream. Now, get ready for the adventure of a lifetime and behold the unfiltered, uncensored, unsubstantiated, and unsportsmanlike experience that is the Eldritch Gamer. Now with absolutely no respect for the Fourth Wall!
Crossover - Cthulhu Mythos & KonoSuba: God's Blessing on This Wonderful World - Rated: M - English - Adventure/Humor - Chapters: 2 - Words: 8,141 - Reviews: 45 - Favs: 292 - Follows: 354 - Updated: 5/24/2021 - Published: 5/6/2021
The Bored Outer God: Through the Ages by Daemon-Sultan reviews
A look at what Nyarlathotep has been up to over the years.
Crossover - Harry Potter & Cthulhu Mythos - Rated: M - English - Romance/Humor - Chapters: 1 - Words: 4,862 - Reviews: 7 - Favs: 13 - Follows: 6 - Published: 5/6/2021 - Complete
Revival by RobbyA reviews
When the family dog is tragically ripped from the mortal coil, Lana meets a strange girl claiming that she has the means of bringing him back.
Crossover - Loud House & Cthulhu Mythos - Rated: T - English - Chapters: 12 - Words: 18,542 - Reviews: 6 - Favs: 8 - Follows: 9 - Updated: 2/21/2021 - Published: 12/26/2019 - Complete
The Horrors from Outer Space by thebrillaintgrandmaster
Crossover with Onyx Path's Scion 1e: Long ago, the Gods of the various pantheons overthrew the Titans, as Fate ordained. Little did the Gods know, the Titans had been holding back something far worse and powerful than anything they could imagine. As the Outer Gates begin to crack, it is up to the Rooks to unite the Pantheons and put the Outer Gods and their spawn back to sleep.
Crossover - Mythology & Cthulhu Mythos - Rated: M - English - Supernatural/Horror - Chapters: 1 - Words: 2,052 - Published: 2/17/2021
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