1Dumb luck: Mandy version by The Cowardly Christian Gender Flipped, Dumb Luck AU! What if Mandy was the one who was cursed with bad luck?
T, English, Humor & Supernatural, words: 848, follows: 1, 7/9, Mandy
1 for my friends by Mario bros fan4ever when Billy fights with Jeff he now has a choice go home or save his friends based on wrath of the spider queen
K, English, Friendship & Adventure, words: 64, 6/25, Billy
1angry Luigi saves Christmas » by Mario bros fan4ever when Santa turns into a vampire Billy and Mandy team up with angry Luigi and alem tuber to find the main vampire
K+, English, Adventure & Humor, chapters: 3, words: 722, updated: 6/25 published: 6/11, Billy, Grim, Mandy, OC
2 Tutor Mindy » by Shaeril McBrown Mindy's mom hired a tutor to help her daughter study well.
T, English, Drama & Hurt/Comfort, chapters: 2, words: 383, updated: 5/23 published: 5/20, Mindy
4 LJ and Zofia's Big Boogey Adventure » by PerkyGoth14 Much to their strong dismay, LJ and Zofia have to go to the Underworld with Billy, Mandy, and Grim when the death reaping skeleton is sentenced to court for misusing his powers and the Boogeyman takes him to court. When Grim's powers are soon taken from them, they are told about Horror's Hand which can make one's fears come alive and Boogeyman intends on taking it for himself.
K+, English, Horror & Adventure, chapters: 8, words: 21k+, favs: 7, follows: 5, updated: 4/1 published: 3/28, Mandy, Grim, Boogey Man, OC
2 Back to the Past » by pinkamena426 Billy and Mandy realize they have old versions of themselves from 1998 and go to visit them. Grim realizes that he's better off with the normal Billy and Mandy.
K+, English, Humor, chapters: 4, words: 830, favs: 1, follows: 2, 3/27, Mandy, Grim, Billy
Sonny by RitzyGreen When Junior first came to the surface world, he stole the appearance of a young boy at winter camp. In doing so, he unknowingly tore that boy's family apart. OC centric
T, English, Angst & Horror, words: 4k+, favs: 1, 3/19, Nergal Jr., OC
5 Make my hips big by Shaeril McBrown Mandy meets a goth girl named Mariella after getting wide hips.
T, English, Humor & Friendship, words: 265, 2/16, Mandy, OC
2Underfist, The series » by Princess Regia Al Ever wonder what happened to Underfist after the movie? Read to find out! PS. Cartoon Network, please renew Maxwell Atoms's contract and make this a TV show!
K+, English, Adventure & Humor, chapters: 6, words: 5k+, favs: 5, follows: 3, updated: 1/16 published: 7/31/2015
5 Fundamentals of a relationship by ecwecwecw1 Billy and Mandy are in High School now. While some parts of there relationship has changed, the Fundamentals are still the same. BillyxMandy, one shot.
T, English, Humor & Romance, words: 4k+, favs: 17, follows: 7, 12/8/2019, [Billy, Mandy] Grim, Mindy
1 LJ and Zofia's Jacked Up Halloween » by PerkyGoth14 LJ, Zofia, and their friends come to celebrate Halloween with Billy and Mandy. However, not all is well when Grim tells them the story about a prankster known as Jack O. Lantern who lived in ancient times, causing tricks for people. Due to Billy's stupidity, he comes back and takes Grim's scythe to make it Halloween night forever so he can conquer the world.
T, English, Supernatural & Horror, chapters: 5, words: 16k+, favs: 5, follows: 5, updated: 10/7/2019 published: 10/6/2019, Mandy, Jack, Billy, OC
1Dreams of Darkness by Treacle Parcheesi As they settle into married life, Nergal decides to reveal to Sis the story of how he grew up and how he came to be banished from the Underworld. In the meantime, the powers that be threaten their future ... a future Sis is keeping a secret for now.
K+, English, Romance & Friendship, words: 2k+, follows: 1, 9/14/2019
Underfist v Irwin Family Reunion » by SteveAtwater They've faced down an evil marshmallow bunny, squid attackers from the underworld, aSTRoVaMPiReS, and spiders. They've grown close...er. They're accepted as Earth's heroes...kind of. But now, Underfist faces its greatest challenge yet...the judicial system!
K+, English, Humor & Supernatural, chapters: 10, words: 12k+, updated: 6/14/2019 published: 5/27/2019
2 All for You by Shaeril McBrown Mandy finds out that she has a voice of a angel.
T, English, Humor, words: 289, favs: 1, follows: 1, 6/8/2019, Mandy
2La profecia by vikipaxa Puro Hueso esta involucrado en una extraña profecía que amenaza tanto el mundo de los mortales como al inframundo, el problema es que Mandy y su primer amor tienen que ver con esto. Por ello de la forma mas indiscreta intentaran encontrar a ese primer amor de la rubia para ver de que forma detienen todo, si es que pueden. (Aviso GrimxMandy)
T, Spanish, Angst & Romance, words: 4k+, favs: 2, follows: 2, 6/2/2019, [Grim, Mandy] Billy, OC
1 See Mandy Dance » by Shaeril McBrown Grim found out that Mandy is dancing.
T, English, Humor & Romance, chapters: 2, words: 561, favs: 1, follows: 1, updated: 4/23/2019 published: 4/13/2019, Grim, Mandy, Mindy
1 LJ and Zofia and the Wrath of the Spider Queen » by PerkyGoth14 LJ and Zofia start going to school with Billy and Mandy, but luckily, their friends Dib, Gaz, Nergal Jr, Kimberly, Chrissy, and even Akito and Estelle will be going with them. It's not a very good first day of class though since there's a spider infestation, and it turns out that the school is going to be held for the Spider Queen for her revenge against the Grim Reaper.
K+, English, Drama & Supernatural, chapters: 6, words: 13k+, favs: 3, follows: 2, 3/18/2019, Mandy, Grim, Billy, OC
2The Journey of Billy and Mandy by CillianChamp Billy and Mandy are teenagers when they accidentally got transport into the Underworld where they must find a way out before the Boogey Man and Nergel will take over Endsville.
K+, English, Adventure & Horror, words: 693, favs: 5, follows: 3, 2/2/2019, [Billy, Mandy] Boogey Man, Irwin
1 Rock-a-Bye Pinhead » by JrNitro24 Based on the SpongeBob episode "Rock-a-Bye Bi-Valve": Billy and Mandy are older now, and find an abandoned child. With no one to take care of him, Billy and Mandy decide to raise him as their own. But with Billy constantly working and never giving Mandy her break, tempers start flaring around the odd couple. This fanfiction is only BillyxMandy if you want it to be.
K+, English, Parody & Humor, chapters: 2, words: 1k+, favs: 2, follows: 2, 11/8/2018, [Billy, Mandy]
1 Tea for Two by MasterMind13 A followup on "The Secret Snake Club." Irwin is released from jail and meets up with a certain macrame club member. A CarolxIrwin oneshot. Request fic.
K, English, Friendship & Romance, words: 896, favs: 2, follows: 1, 10/16/2018
Mandy's Halloween Treat by DyNaMoDave In this story, Mandy decides to give a very special Halloween treat to someone who helped her on her first Halloween.
K, English, words: 2k+, favs: 2, follows: 1, 10/8/2018
1I know who killed me » by DarkHime213 Only the journal entries can show the true killer. Billy, Irwin, Mindy, Nergal. . . . . Oh, who could it be if its even one of them.
T, English, Mystery, chapters: 4, words: 3k+, favs: 1, updated: 9/6/2018 published: 8/23/2018, Billy, Mindy, Nergal Jr., Irwin
Underfist: Return of the Spider Queen » by SteveAtwater After facing down the aSTRoVaMPiReS, Underfist learns of an all-new threat seeking to take over the world–and this new threat is led by Velma Green! Will Underfist be able to stop the Spider Queen? Will Fred Fredburger eat nachos and frozen yogurt? Will there be cobwebs everywhere? Find out the answers to these questions and more in Underfist: Return of the Spider Queen!
K+, English, Humor & Adventure, chapters: 10, words: 9k+, favs: 2, updated: 8/14/2018 published: 8/10/2018
1 Do Over by MasterMind13 An extended ending to "The Greatest Love Story Ever Told." In which Nergal Jr. apologizes to a certain girl.
K, English, Hurt/Comfort & Romance, words: 819, favs: 4, 6/10/2018
3 Underfist Against the aSTRoVaMPiReS » by SteveAtwater The long-awaited sequel to Underfist: Halloween Bash...is never coming out. Why? Because Cartoon Network didn't renew Maxwell Atoms's contract a decade ago. Instead, there's this: a fanfiction attempting to continue the story of Underfist. Join Irwin, Fred, Hoss, Jeff, and Skarr as they take on their biggest challenge yet: the aSTRoVaMPiReS!
K+, English, Humor & Supernatural, chapters: 10, words: 9k+, favs: 3, updated: 5/16/2018 published: 4/19/2018