If Broly crosses over into the DC universe, Superman could potentially be an ally. They both have superhuman strength and are from other planets. Superman could try to guide Broly on how to use his power responsibly and help him control his rage.
In a crossover with the Naruto universe, Naruto himself could be an ally. Naruto has a way of seeing the good in people, and he might try to reach out to Broly and convince him to use his power for good. His ability to befriend and understand others could be key.
In a crossover with One Piece, Luffy could be an ally. Luffy is known for his open - mindedness and ability to befriend almost anyone. He would see Broly's power and might try to get him to join his crew or at least fight alongside him against common enemies. They could have some really fun interactions, like Luffy trying to make Broly laugh or share his love for food with him.
One idea could be that Godlike Broly crosses over into the Dragon Ball Super universe and challenges Goku and Vegeta at their peak forms. His overwhelming power could force them to seek new power - ups and training methods.
Goku could be a likely ally. Despite their initial conflicts, Goku has a way of seeing the good in people. He might approach Broly and convince him that they can work together to win the Tournament of Power for their universe. Their combined strength would be a formidable force.
Vegeta could also be an interesting choice. Vegeta has his own pride and issues with power, much like Broly. In a crossover fanfiction, they could start off as rivals, constantly trying to outdo each other in terms of strength. But as the story progresses, they might find common ground and have to work together against a common enemy. This would be a great way to explore both of their characters in more depth.
Trunks would also be a great choice. Trunks is from the future and has a different set of skills and experiences. He could introduce Broly to some new technology or fighting techniques from his own timeline. And together, they could face threats that neither could handle alone, like a time - traveling villain.
One idea could be that Broly somehow ends up in the world of Black Lagoon. He might initially be seen as a huge threat by the Lagoon Company. But as the story progresses, they realize his power can be useful against their common enemies. For example, when facing powerful crime syndicates or military forces that are too much for them to handle alone.
Definitely Goku. Their previous encounters in the Dragon Ball series make it a natural choice. Their power levels and different fighting styles would create great tension and action in the story.
A third common theme could be the exploration of different universes. The fanfictions might delve into how the Dragon Ball universe, where Broly comes from, and the RWBY universe coexist or affect each other. This can include things like different laws of physics, magic systems, and cultural differences between the two universes.
DBS Broly is considered stronger. He has more advanced powers and abilities shown in the manga.
A 'godlike Madara' in a crossover fanfiction could be really interesting. It might involve Madara from Naruto being given 'godlike' powers and then being crossed over into another universe, like a different anime or even a fictional world from a game. This could lead to some really epic battles and unique storylines.