One idea could be that the Hulk somehow gets transported to the DC universe. Maybe due to a freak accident involving some sort of interdimensional portal created by Lex Luthor in an attempt to bring in a powerful being to defeat Superman. The Hulk then starts rampaging through Metropolis, and Superman has to figure out how to stop him without causing too much destruction himself. He tries to reason with the Hulk at first, but when that doesn't work, he has to use his strength and speed to keep the Hulk occupied until they can find a way to send him back to his own universe.
Superman would be really interesting. Their powers are quite different. Superman is an alien with a wide range of powers like flight, super - strength, heat vision etc. The Hulk, on the other hand, is a being of pure rage with ever - increasing strength. Their encounter could be a clash of ideologies as well. Superman stands for truth, justice and the American way, while the Hulk is often just a force of destruction when enraged. It would be fascinating to see how Superman tries to calm the Hulk down or how the Hulk reacts to Superman's attempts at peacekeeping.
The Scarlet Witch is a great candidate for a crossover with She - Hulk. Her reality - warping powers and She - Hulk's physical might could create some really unique storylines. Maybe Scarlet Witch accidentally warps reality in a way that affects She - Hulk's powers, and they have to work together to fix it. Also, Ant - Man could be fun. She - Hulk could be accidentally shrunk by one of Ant - Man's devices and they have to figure out how to reverse the process while also dealing with threats in the micro - world.
Another idea is that Greninja gets exposed to some kind of meta - human - creating substance in the DC universe and gains new powers. It could then join the Teen Titans, sharing its unique Pokémon abilities with the group. It would be interesting to see how Greninja interacts with characters like Robin, Starfire, and Cyborg, and how it uses its powers in battles against the Titans' enemies.
One common theme is the exploration of power dynamics. When the Hulk crosses over with other characters, it's all about how their powers compare and interact.
One of the great things about a World War Hulk crossover fanfiction is the potential for character growth. Hulk, who is already a complex character, can be further developed. Maybe he learns to control his anger in a different way when faced with new challenges in the crossover. Also, other characters involved in the crossover can have their own arcs. For instance, if a less - known character from another universe teams up with Hulk, they might gain more popularity and depth through this fan - created story.
One idea could be that the Hulk somehow gets transported to the wizarding world. Maybe a magical experiment gone wrong by a Hogwarts student creates a portal. The Hulk's brute strength would be a shock to the wizards and witches. He could end up causing chaos in Hogwarts, knocking down walls and scaring students. Wizards would try to use spells on him, but his strength might make him resistant at first.
One interesting concept could be a crossover battle between Hulk and DC's strongest characters like Superman. Imagine the clash of their superhuman strength and different power sets. It would be a spectacle of epic proportions.
It depends on the situation. In terms of raw physical strength, the Hulk is incredibly powerful. He can smash through mountains with ease. But Naruto has his own set of skills. His ninjutsu, like the Rasengan, can cause a great deal of damage. Also, Naruto has the power of the Nine - Tails, which gives him a huge boost in chakra. If they were to fight in an open field, the Hulk might have the upper hand in a direct physical clash. But if Naruto can use his ninja skills to his advantage, like creating diversions with clones and hitting the Hulk from unexpected angles, he could potentially win.
In this crossover fanfiction, the Hulk's strength could be used to help the Loud family in a big way. For example, there could be a natural disaster about to hit Royal Woods, like a huge flood or an earthquake. The Hulk, with his superhuman strength, could hold back the floodwaters or stop the shaking ground. Meanwhile, the Loud kids could be helping the townspeople evacuate. It would be a story of how two different universes come together to save a town.