One idea could be that Thorin and Bilbo are exploring an old, abandoned mansion together. They discover hidden rooms filled with ancient treasures and must face various traps and puzzles to get out safely.
Well, a great plot for a Harry Potter mansion fanfic could be centered around a lost heirloom. The mansion was once owned by an important wizarding family, and a valuable heirloom has been lost within its many rooms and corridors. The characters embark on a quest to find it, facing various challenges like magical traps and puzzles. Also, the mansion could be a place where time behaves differently. People who enter might find themselves in different eras of the wizarding world, and they have to find their way back to the present while also uncovering the secrets of the mansion's past.
Balin could be a great supporting character. He is wise and could offer advice to Thorin and Bilbo as they explore the mansion. Maybe he knows some secrets about the place from his past.
A plot could revolve around Luigi having to rescue all the Toads that have been scattered throughout the mansion in different forms - some are invisible, some are trapped in paintings. As he searches for them, he uncovers secrets about the mansion's original owner and their dark past.
Well, perhaps the Harry Potter mansion in the fanfiction could be a place where a secret society of dark wizards once resided. The main characters stumble upon it and find clues about a long - forgotten dark magic plot. Or it could be a mansion that has been enchanted to change its layout constantly, like a magical maze. And it might also be the place where a powerful magical object was created, and now everyone is after it.
A third idea is to cross it with a post - apocalyptic world. The haunted mansion becomes a refuge in a desolate world. However, it has its own set of challenges as the ghosts and spirits within the mansion are not used to the new outside threats. The survivors from the apocalypse have to team up with the mansion's spectral inhabitants to defend against new, more dangerous threats.
Maybe an OC that is a ghost hunter from another dimension comes to Luigi's Mansion. This OC has advanced ghost - hunting tools and techniques that Luigi has never seen before. Together, they team up to face an extremely powerful and malevolent ghost that has been terrorizing the mansion for a long time.
One idea could be exploring the backstory of the mansion itself. Maybe it was once a normal house before the spooky events started. Another could be focusing on a particular character's experience inside the mansion, like how they deal with the constant jumpscares. And a third idea might be to create a story where the characters find a way to break the curse of the mansion.
Well, perhaps a plot where the characters are trying to solve the mystery of the previous owners of the mansion. They find old diaries and photos that lead them on a wild goose chase filled with creepy revelations about the mansion's past. For example, they might learn about some dark rituals that were once performed there, which adds to the overall spooky atmosphere of the fanfic.
One great 'bagginshield fanfic' is 'The King's Consort'. It beautifully portrays the relationship between Bilbo and Thorin. Another is 'A New Adventure' which takes their story in a really interesting and unexpected direction. And 'The Shire's Gift' is also a wonderful one that shows how their bond affects the whole of Middle - earth.
One idea could be a story where the characters discover a hidden room in the haunted mansion that holds the key to the mansion's dark past. Another could be about a group of friends who get trapped in the mansion during a storm and start experiencing strange paranormal events. Maybe a story where a character has the ability to communicate with the spirits in the mansion and tries to help them find peace.