Perhaps in this fanfiction, the Civil War is not just between the heroes but also involves some villains who see it as an opportunity to take over. A villain could be secretly manipulating both sides of the conflict, making it seem worse than it really is. A hero discovers this plot and has to convince both factions that they are being played. This could lead to a reluctant truce as they join forces to take on the real enemy. It could also explore how trust is rebuilt among the heroes after such a huge deception.
A plot could involve a group of young, inexperienced heroes who idolize the Avengers but are horrified by the Civil War. They form their own little group and try to show the older heroes how they can resolve their differences. For example, they might set up secret meetings where they exchange ideas and slowly start to bridge the gap between Captain America and Iron Man's sides. They could also face challenges like being hunted by the authorities who see them as interfering in a complex situation.
One idea could be that a new hero emerges during the Civil War and tries to find a middle ground between the two factions. They might have unique powers that allow them to communicate with both sides on a deeper level, and they end up uniting some of the heroes against a common, unexpected threat that was using the Civil War as a distraction.
A common plot idea is time travel. The heroes could go back in time to before the events that led to the Civil War and prevent them from happening. For instance, they could stop the creation of the Sokovia Accords or resolve the issues that made the heroes split in the first place.
Well, you could also have a plot where the secrets that were buried during the civil war start to surface in the aftermath. Maybe there were hidden alliances or betrayals that now come to light and create new tensions. It could involve characters having to deal with the truth about their past actions or the actions of their loved ones.
One idea could be Gohan getting transported to the Marvel universe and teaming up with the Avengers. He could use his Saiyan powers to help them fight against Thanos. Maybe his energy blasts would be a new weapon against the powerful foes in the Marvel world.
One idea could be Sans from Undertale ending up in the Marvel universe. He could use his shortcuts and bone attacks to fight alongside the Avengers against a common enemy like Thanos. His laid - back attitude would contrast with the more serious heroes in Marvel.
One idea could be that Superman gets transported to the Marvel universe during a freak interdimensional event. He teams up with the Avengers to fight a common enemy like Thanos, who has somehow obtained Kryptonite. Their combined powers and different strategies would make for an epic battle and an interesting exploration of how the two universes' heroes interact.
Maybe in the fanfiction, Cortana could be integrated into Iron Man's suit. Her advanced AI could enhance the suit's capabilities even further. And they could work together to take on a new villain that is causing chaos in both the Halo and Marvel worlds. It would be a great mix of science - fiction elements from both universes.
One plot idea could be that the vampires from Twilight possess some of the superpowers from the Marvel universe. For example, Edward could have Wolverine's healing factor in addition to his vampire abilities. This would make him even more indestructible and add a new layer to his character.
One idea could be that Ben Tennyson's Omnitrix gets mixed up with some of the Infinity Stones' energy. This causes his aliens to gain new powers related to the Stones. For example, Four Arms could have super strength on a whole new level like Hulk. Another plot could be that the heroes from both universes have to team up to fight a villain who is using technology from the Ben 10 world and magic from the Marvel universe. Maybe a new character who has stolen some of Doctor Doom's knowledge and some of Vilgax's power.
One plot idea could be Naruto being transported to the Marvel Universe during a strange space - time rift. He might team up with Spider - Man. Naruto's ninja skills like shadow clones and rasengan could be a great asset in battles against Marvel villains. Another idea is that the Infinity Stones somehow end up in the Naruto world, and the Avengers have to go there to retrieve them, leading to a clash and then an alliance between the two groups.
One idea could be that the Infinity Stones are somehow connected to the Warp in the Warhammer universe. Maybe Thanos discovers a way to tap into the power of the Warp through the Stones, which brings the heroes of Marvel into conflict with the daemons and factions of Warhammer.