I think the combination of the Doom Slayer and Anya Oliwa from Wolfenstein could be really interesting. Anya is a strong and intelligent character. She could provide the Doom Slayer with valuable information about the Wolfenstein world, like the layout of Nazi bases and their technology. Meanwhile, the Doom Slayer could protect her with his incredible combat prowess. This dynamic could lead to a story where they work together to uncover a deeper conspiracy that links the demons and the Nazis.
The Doom Slayer and Deathshead from Wolfenstein would be an intense combination. Deathshead is a brilliant but evil scientist. If the Doom Slayer were to face him, it would be a battle of brute force against scientific genius. The Doom Slayer could be trying to stop Deathshead from using his knowledge to create even more powerful and dangerous weapons or even combine the power of the demons with Nazi technology. This would be a high - stakes encounter with lots of action and drama.
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.
It could be a new entity that combines the worst aspects of both universes. For example, a Nazi scientist who has managed to merge demonic powers with his own dark experiments. This character would be extremely powerful, having the strategic and technological knowledge of the Nazis along with the raw, otherworldly power of the demons.
I think Ben's Heatblast and Thor would be an interesting combination. Heatblast can generate intense heat and fire, while Thor has his lightning powers. They could create some really powerful elemental attacks together.
Carly and Jade could be really cool together. Carly is sweet and friendly, while Jade is edgy and a bit of a troublemaker. Their interactions would be full of contrast. Carly might try to soften Jade a bit, and Jade could introduce Carly to a more rebellious side of life in Hollywood Arts.
Frisk and Chica would also be a cool combination. Frisk is all about kindness and determination, and Chica is this animatronic with a bit of a goofy side. Frisk could try to understand Chica's motives and maybe even help her find a new purpose other than scaring people at night.
Definitely Spider - Man and Mr. Incredible. Mr. Incredible has brute strength and experience in dealing with super - villains. Spider - Man, on the other hand, has his acrobatic skills and spider - sense. Their combination would be interesting as they could learn from each other's combat styles. Mr. Incredible could teach Spider - Man how to use his strength more effectively in close - quarters combat, while Spider - Man could show Mr. Incredible how to be more agile and use the environment to his advantage with his web - slinging.
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.
The Doom Slayer and a Space Marine would be really interesting. They both are combat - focused and have a strong sense of duty. They could start off as rivals, each thinking their way of fighting is superior, but then come to respect each other after facing a common enemy like the forces of Chaos.
In a Doom and Wolfenstein crossover fanfiction, it could be that there is a portal that opens between the two worlds. The demons start pouring into the Wolfenstein world, and BJ has to reach out to the Doom Slayer for help. The Doom Slayer brings his arsenal of powerful weapons, and together they train the resistance fighters in Wolfenstein to use these weapons. They also discover that some of the Nazi technology can be modified to be more effective against the demons, creating a unique blend of combat strategies from both universes.