In this fanfic, perhaps the walled cities in Attack on Titan are actually a result of some sort of ancient experiment by an alien race similar to the Kree or the Asgardians in Marvel. The characters from both worlds would then have to figure out the truth behind this while also dealing with the threats of Titans and other Marvel - related menaces. The Titans' regenerative abilities might be something that the Marvel scientists like Bruce Banner would be very interested in studying.
Well, it could be about the Survey Corps teaming up with the Avengers. Maybe Eren's titan form could be as strong as the Hulk in a battle against a common enemy like Thanos. The Scouts' ODM gear would be an interesting contrast to the high - tech gadgets of the Marvel heroes.
A possible plot could involve the Nine Titans being some sort of ancient power that Marvel villains are after. The Avengers would then have to work with the characters from Attack on Titan to protect these powers. For example, Captain America could lead the human soldiers alongside Levi, and they would strategize on how to keep the Titans and the Infinity Stones out of the wrong hands. It could also explore how the different powers and abilities in both universes interact with each other.
Well, it could be about the Survey Corps finding a crashed Cybertronian ship. Maybe the Titans are somehow related to a Decepticon experiment gone wrong. The Scouts would then team up with the Autobots to fight both the Titans and the Decepticons.
Well, it could be about Eren Yeager somehow getting transported to the Naruto world. Maybe he teams up with Naruto to fight against a common enemy like the Akatsuki who have somehow gotten their hands on Titan powers. They would have to combine their unique skills, Eren's Titan transformation and Naruto's jutsu.
I think Eren and Spider - Man could make a great pairing. Eren has his determination and the power of the Titans, and Spider - Man has his agility and quick thinking. They could learn a lot from each other in terms of fighting skills and moral values.
Well, it could be amazing. Imagine the Survey Corps teaming up with the Avengers. Eren could use his Titan powers alongside Thor's godly strength. Maybe they'd be fighting a common enemy like Thanos who has somehow made his way to the Attack on Titan world. The different powers and personalities would create really interesting dynamics.
One common theme is power struggle. Both 'Attack on Titan' and Marvel have characters with great powers. In the fanfics, it's often about how the powers from 'Attack on Titan' like the Titan - shifting abilities compare and interact with the superpowers in Marvel.
The cultural clash. The Marvel heroes come from a world with a different set of values compared to the more survival - based world of Attack on Titan. Seeing how they interact and try to understand each other's motives would be really engaging. For example, Steve Rogers might try to instill his sense of justice and freedom in the characters of Attack on Titan, while they might show him the harsh realities of their world.
A really cool plot could be that some of the Attack on Titan characters gain superpowers from the Marvel universe. For example, Mikasa could get some sort of enhanced combat abilities like Black Widow's training but on steroids. And the Survey Corps could learn new technology from Tony Stark to better fight the Titans. Also, Loki could play a devious role in the crossover, causing chaos between the two worlds by manipulating both sides.
One possible plot could be that the Titans somehow cross into Spider - Man's universe. Spider - Man initially mistakes them for some new kind of giant robots or mutants. He tries to fight them using his web - slinging and acrobatic skills. But he quickly realizes they are much more difficult to defeat as they keep regenerating. Meanwhile, some of the Survey Corps members from Attack on Titan also cross over. They team up with Spider - Man, teaching him about the Titans' weak points at the back of their necks. Together, they fight to keep both universes safe from the Titans.
One common theme is the clash of different power systems. For example, when crossing over with a magic - based series, the contrast between the Titans' brute force and magic is explored.
The story could begin with Optimus Prime leading the Autobots to a new dimension in search of a powerful energy source. This dimension turns out to be the world of Attack on Titan. The Survey Corps mistakes the Autobots for new threats at first. However, Armin, being the intelligent one, quickly realizes that they might be able to help in the fight against the Titans. Meanwhile, Megatron and some Decepticons also arrive. They see the Titans as potential weapons or servants. The Autobots then form an alliance with the Survey Corps. Optimus Prime is impressed by the courage of the humans, especially Mikasa Ackerman. As they battle the Titans together, the Autobots teach the humans about advanced technology, and the humans show the Autobots the importance of unity and tenacity in the face of a seemingly unbeatable enemy.