To blend the two universes' rules, we could start with the idea that the Forerunners were actually an ancient civilization that had a connection to magic long ago. So their technology is based on a forgotten form of magic. Sunset Shimmer could be the key to unlocking this forgotten knowledge. In terms of combat, the shields in Halo could be seen as a form of magical protection similar to the spells Sunset can cast. And the way the Spartans move and fight could be enhanced by Sunset's knowledge of movement spells.
One way is through a crossover event. Maybe a portal opens up between the two universes. Characters from each side then enter the other's world and have to deal with the new environment and threats. For example, the RWBY team could find themselves on a Halo ring and have to fight the Covenant alongside the Spirit of Fire crew.
One interesting plot could be Sunset Shimmer getting transported into the Halo universe. She might use her magic skills to help the UNSC in unexpected ways, like creating magical barriers to protect against Covenant attacks. Another plot could involve a Halo character coming to Sunset's world and having to adapt to the magic there.
In Naruto in Overwatch fanfiction, the concept of elemental jutsu can be really interesting. Naruto's fire - style jutsu could be related to some of the fire - using heroes in Overwatch like Ashe. His water - style jutsu could be used in a creative way, like for defense or to put out fires in the Overwatch maps. And the idea of chakra could be something new to the Overwatch universe. It could be a power source that some characters start to tap into, leading to new abilities and power - ups.
Another way is to have a character from one universe end up in the other, like Venom ending up in the Young Justice world. Then, through that character's eyes, we can explore the new universe and see how it clashes or meshes with their own. You could also introduce some sort of magic or technology that bridges the two universes, like a portal - creating device that was created by a mad scientist in both universes independently, but when activated, it links the two. This would bring in elements of mystery and discovery as the characters figure out how to use it and what it means for their respective worlds.
One way to blend the Batman and Pokemon universes in fanfiction could be by having Batman encounter Pokemon in Gotham. Maybe some villain has found a way to bring Pokemon into his world and is using them for evil deeds. Batman would then have to figure out the nature of these strange creatures while also dealing with the chaos they cause.
Well, you can start by having the settings interact. For instance, the forest in 'Into the Woods' could connect to the forested areas around Forks in 'Twilight'. The characters' traits can also be combined. The vampires' elegance and strength in 'Twilight' could be paired with the cunning of some 'Into the Woods' characters like the fox. Also, the magical elements from 'Into the Woods' like spells and wishes could influence the events in the 'Twilight' universe.
One way to blend the two universes could be through character crossovers. For example, imagine a Pokemon trainer like Ash in the world of Westeros. He could use his Pokemon to help in battles or in diplomatic situations. His Pikachu's electric attacks could be used as a weapon or a deterrent in the political power plays of the Seven Kingdoms. Another aspect could be the introduction of Pokemon into the Game of Thrones ecosystem. Maybe some Pokemon could be native to certain regions of Westeros, like ice - type Pokemon in the North. This would add a new layer of complexity to the already rich lore of Game of Thrones.
One way is through character crossovers. For example, a character from Warcraft like Arthas could be transported to the Game of Thrones world. His dark powers and complex backstory would create interesting dynamics with the power - hungry characters in Westeros. Maybe he would be seen as a new threat or a potential ally by different factions.
The aesthetics blend in interesting ways. In Halo, you have the bright, energy - based elements like the plasma weapons. When combined with Warhammer's dark and moody aesthetic, it can create a unique look. The Forerunner architecture in Halo, with its large, geometric structures, can be juxtaposed with the gothic spires and cathedrals of Warhammer. It's like a meeting of the future and a dark, fantastical past. You might see a Halo UNSC base built within the ruins of a Warhammer city, or vice versa, and the different styles would clash and merge in a visually appealing way.
You can blend the two universes by focusing on their common themes. For example, both Sonic and Hello Kitty are about friendship. So, a story could be built around the concept of making new friends across different worlds. Have Sonic meet Hello Kitty's friends like My Melody and they all learn from each other's positive qualities.