Well, it could be about the RWBY characters finding themselves in the Doom universe. Maybe Ruby and her team are trying to fight off the demons in Doom while also using their own unique abilities. They might team up with the Doom Slayer at some point to take on a big, bad enemy that threatens both universes.
One idea could be the Doom Slayer arriving in the RWBY world. He could be on a mission to stop some sort of demonic invasion that has seeped into Remnant. His powerful arsenal and unwavering determination would be a huge contrast to the Huntsmen and Huntresses of RWBY.
A possible plot is that a portal opens between the Doom universe and RWBY's. Some of the Doom demons start spilling into Remnant, the world of RWBY. Ruby and her team initially mistake them for a new, extremely powerful type of Grimm. As they try to fight them, they realize they need different strategies. Meanwhile, the Doom Slayer follows the demons through the portal to stop them. Eventually, the two groups meet and learn from each other's combat styles to defeat the invading demons.
Blake could be a very interesting character in a RWBY Doom crossover fanfiction. Her ability to create illusions and her cat - like reflexes could give her an edge in the Doom universe. Also, her complex backstory and her more reserved nature compared to some of the other RWBY characters would make for an interesting dynamic when interacting with the Doom Slayer and the other denizens of the Doom world. She might be able to use her stealth to sneak up on demons or create illusions to distract them while the others attack from different angles.
The Doom Slayer and Ruby. Ruby is young and full of hope, always looking for adventure. The Doom Slayer is a stoic, battle - hardened warrior. Their interaction would be really interesting. Ruby could be in awe of his strength and weapons, and the Doom Slayer might see a bit of his own unwavering will in Ruby.
The Doom Slayer and Ruby would be an interesting pairing. Ruby is young and full of energy and hope, while the Doom Slayer is a silent, stoic force of destruction against evil. Their interactions could be really cool, like Ruby trying to understand the Doom Slayer's lack of words but seeing his determination and being inspired by it. And the Doom Slayer might see Ruby's potential and unwavering spirit in the face of danger as something similar to his own.
One possibility in this fanfiction could be that Naruto's positive and determined nature clashes with Doctor Doom's tyrannical and power - hungry ways. Maybe Naruto is transported to Doctor Doom's world and tries to bring his sense of justice there. He might use his ninja skills to outwit Doom's high - tech defenses.
There's 'Doom Patrol's Adventure in the Arrowverse'. This fanfiction takes the Doom Patrol and drops them into the Arrowverse. It's exciting as it allows for crossovers with characters like the Flash and Green Arrow. The Doom Patrol's surreal abilities and backstories add a whole new layer of complexity and fun to the Arrowverse.
One great Doom Slayer crossover fanfiction is the one where he crosses over with the Halo universe. It's exciting to see the Doom Slayer's brute force combined with the high - tech weaponry of Halo. The way the two different art styles and storylines blend is really engaging.
A good 'Good Doom Crossover Fanfiction' has well - integrated universes. For example, if it's a crossover with 'Metroid', the different technologies and atmospheres of both Doom and Metroid need to blend smoothly. The Doom Slayer's movements in the more enclosed and alien - like environments of Metroid should feel natural.