What could be an interesting plot for a Spider - Man and Fantastic Four crossover fanfiction?

Perhaps a reality - warping villain decides to merge the universes of the Fantastic Four and the Avengers in a chaotic way. Characters start to forget who they are and where they belong. Spider - Man, who is sometimes associated with the Avengers, teams up with the Fantastic Four to try and restore order. They have to travel through different dimensions that are now all jumbled together. The Fantastic Four's Human Torch could provide light and heat in the dark and cold dimensions they encounter, while Black Widow uses her combat and espionage skills to gather information about the villain's plans.

Well, a cool plot might be about a new super - powered villain emerging. This villain has the ability to steal powers from both the Avengers and the Fantastic Four. The two teams join forces. Captain America takes charge in terms of strategy. Sue Storm uses her invisibility and force fields to protect the team from surprise attacks. Hulk and the Human Torch could have an interesting dynamic, with the Hulk being impressed by the Torch's fire - based powers and the Torch being a bit intimidated by the Hulk's raw strength at first.

One idea could be that Spider - Man somehow gets transported to the Underground in Undertale. He might initially be confused but quickly adapts his powers to the new environment. For example, he could use his webs to swing through the caverns and his spider - sense to detect approaching monsters. Maybe he teams up with Sans and Papyrus to fight against a common enemy, like a new, powerful and evil entity that threatens both the Underground and New York City in some way.

In fanfiction, if Spider - Man joins the Fantastic Four, there could be some really cool team - up scenarios. They might face new and more powerful villains together. For example, they could take on a super - intelligent alien that requires both Spider - Man's agility and the Fantastic Four's unique powers to defeat.

Sue Storm could be a great character to focus on. In a crossover, she could use her force fields in new and creative ways. Maybe she has to protect Spider - Man from some of his more dangerous enemies when he's outnumbered. Also, her relationship with Reed Richards could be explored further in the context of a crossover. How would she react to Spider - Man's more impulsive nature? And how would she use her powers to help Spider - Man and the Fantastic Four work together more effectively? There are a lot of interesting storylines that could be developed around her.

One interesting crossover could be Spider - Man and The Fantastic Four teaming up to fight a powerful new villain that neither could defeat alone. Maybe a villain with the ability to manipulate time and space, forcing them to combine their unique powers.

Perhaps Spider - Man would be initially distrusted by the Fantastic Four. He is a bit of a lone wolf compared to their more family - like dynamic. But then they would realize his good intentions and start to work together. For example, he could use his web - slinging to help Mr. Fantastic reach places during a rescue mission, while the Invisible Woman could provide cover for Spider - Man when he's outnumbered.

One possible plot could be that they team up to stop a powerful villain who has the ability to travel between their two cities. Maybe this villain is stealing tech from Gotham and super - powers from New York. They start off not trusting each other as they have different methods. Nightwing is more stealthy and trained in combat, while Spider - Man is more quippy and uses his webs in a very acrobatic way. But as they face challenges together, they learn to work as a team and combine their skills to take down the bad guy.

One possible plot could be that Spider - Man gets transported to the RWBY universe. He might initially be confused by the Grimm and the Huntsmen and Huntresses. Maybe he teams up with Team RWBY to fight a new type of threat that combines the technology - based villains from his world and the Grimm from RWBY. For example, a villain could be using some sort of Dust - powered tech to create super - Grimm. Spider - Man's agility and web - slinging abilities would be a great addition to the RWBY team's combat styles.

If it's a crossover with the Fantastic Four, perhaps a cosmic entity is attacking Earth. Spider Man teams up with them to stop it. But during the battle, he's exposed to some deadly radiation from the entity. Despite the Fantastic Four's efforts to save him, his body can't withstand it, and he dies. His death could lead to the Fantastic Four creating new safety protocols for future battles.