You could do a crossover with the Witcher series. Geralt might be intrigued by the different monsters in Guild Wars 2 and how they compare to the ones he's used to slaying. The sylvari, with their connection to nature, could have an interesting dynamic with the druids in the Witcher world. Maybe there could be a quest where they have to work together to stop a common threat.
One idea could be a crossover with the Transformers Prime series. Imagine the Beast Wars characters interacting with the more modern Transformers designs and storylines from Prime. It could lead to some really cool battles and character development as they learn from each other's different ways of dealing with the Autobot - Decepticon conflict.
For 'food wars crossover fanfiction', you could consider a crossover with 'One Piece'. The Straw Hat Pirates could land on an island where the only way to progress is by winning a cooking war. Also, a crossover with 'Fairy Tail' would be cool. The mages could use their magic to create amazing and magical dishes in a cooking showdown. And a crossover with 'Attack on Titan' might involve the Scouts having a food competition to boost morale within the walls.
One idea could be to cross Halo Wars with another popular sci - fi franchise like Star Trek. Imagine the Covenant and the Federation having to deal with each other. Another idea is to have a crossover with a fantasy world, like Lord of the Rings. Maybe the Spartans end up in Middle - earth fighting alongside the elves and dwarves against a new threat that has elements of the Flood. A third idea could be a crossover with a post - apocalyptic world. The Halo Wars units could be trying to survive in a world full of mutants and scarce resources.
For a Star Wars Clone Wars crossover fanfiction, you could explore the idea of a group of Mandalorians from different time periods coming together during the Clone Wars. They might have different views on the war and the Jedi. Some could be more traditional, while others might be influenced by the changing politics of the galaxy. Their presence could add a new layer of conflict and intrigue. They could interact with Clone Troopers, Jedi, and even the Sith in unexpected ways, leading to some epic battles and character - development moments.
One idea could be to cross it with another sci - fi universe like Star Trek. Imagine the Jedi and the Federation crew working together. Another could be a crossover with the Transformers universe, where the clones team up with the Autobots to fight a common enemy. Maybe also a crossover with the Mass Effect universe, with the clones and Shepard's crew sharing combat strategies.
One idea could be that the Jedi and the Avengers team up to fight a common enemy like Thanos who has somehow acquired Sith powers. The Jedi's mastery of the Force combined with the Avengers' unique abilities would make for an epic battle.
One idea could be that Ben uses his Omnitrix to transform into alien forms that have unique abilities to survive in the Star Wars universe. For example, a heat - resistant alien to withstand the heat of Tatooine's deserts or a species with enhanced senses to navigate the dangerous jungles of Kashyyyk. Another idea is that the Galactic Empire somehow gets hold of the Omnitrix and tries to use it for their own evil purposes, leading to Ben having to team up with the Rebel Alliance to get it back.
One idea could be to have the mobile suits from Gundam integrated into the Star Wars universe's battles. For example, the RX - 78 - 2 Gundam could be a new type of powerful mecha that the Rebel Alliance discovers and uses against the Empire. Another idea is to have the Jedi and Sith interact with the Newtype pilots from Gundam. Maybe a Jedi could sense the unique abilities of a Newtype and try to train them in the ways of the Force.
Another concept is that a new threat emerges that requires both the skills of the Avengers and the powers of the Star Wars characters. This new enemy could be a powerful being that can manipulate time and space. The Avengers' superhuman abilities combined with the Jedi's connection to the Force would be needed to defeat it. Black Widow could use her espionage skills to gather intelligence within the Star Wars universe, while Spider - Man (if he's part of the Avengers in this fanfic) could use his agility to navigate the complex terrains of different Star Wars planets.
Another plot idea is a crossover with a time - travel themed story. The characters from Summer Wars are sent to different time periods, like ancient Rome or the future. They have to adapt to the new cultures and technologies while also trying to find a way back home. Along the way, they might change historical events or gain knowledge that will help them save their own world from a potential threat.