Harry could try to communicate with the magical creatures that exist in the Muggle world, albeit secretly. Maybe there's a phoenix nearby that could sense his distress and come to his aid. Or he could use his Parseltongue ability to control a snake to create chaos among the Muggles and then escape in the confusion. Another option is that he could try to make the Muggles believe that he is sick and needs to be taken to a hospital. Once there, he could find a way to contact the wizarding world and get rescued.
He could use his wandless magic. Harry has shown some ability for wandless magic before. He might use it to unlock the doors or create distractions to escape. For instance, he could make a loud noise to draw the Muggles away from the exit and then make a run for it.
One way Harry could escape is by using his knowledge of the Muggle world against his kidnappers. He could pretend to be compliant and then when they least expect it, he could use something like a telephone to call the Weasleys' Wizard Wheezes' phone which is actually a secret passage to the wizarding world. Also, he could try to befriend a Muggle animal like a dog and get it to help him in some way.
In such a fanfiction, Harry might face a great deal of confusion. Muggles don't understand magic, so they might be both frightened and curious about him. They could try to study him like some sort of strange phenomenon. Harry, on the other hand, would be in a tough situation as he is used to the wizarding world and its ways. He might try to escape by using his magic subtly, but he would also have to be careful not to expose magic to Muggles which is against wizarding law.
In such fanfiction, Muggles can be shown in different lights. Some portray them as simple and uncomplicated, living their ordinary lives without any knowledge of magic. However, there are also fanfictions where Muggles are more curious or even a bit envious of the magical abilities of Wizards. They might be depicted as trying to find out about the wizarding world despite the secrecy.
He could use his Invisibility Cloak. The Avengers might not be able to detect it with their technology. Then he could find a way to apparate out if he's far enough from any anti - apparition charms.
Harry could use a powerful disillusionment charm. This would make him blend in with his surroundings so well that SHIELD agents would have a hard time finding him. He could then make his way to an exit while they're distracted. Also, if he had his wand on him, he could perform a series of diversionary spells, like creating a false image of himself to draw their attention away while he escapes.
'Him' could be a centaur. In the Harry Potter universe, centaurs are intelligent and powerful beings. Harry might ride a centaur in a situation where he needs to quickly cross the forest and the centaur's speed and knowledge of the terrain would be very useful.
When it comes to muggles adapting to Hogwarts in fanfiction, it's a complex process. At first, they'd be amazed by the architecture, the talking portraits, and all the magical elements. To adapt, they would need to be open - minded. They'd have to study hard to understand magic, from the simplest charms to the more complex spells. There would be cultural differences too, like the wizarding traditions that they'd have to learn. But as they make friends and start to feel at home, they would slowly become part of the Hogwarts fabric.
Muggles can be a source of conflict. If a wizard falls in love with a muggle, they have to deal with the secrecy of the wizarding world and potential disapproval from both sides. This can drive the plot in many different directions, like trying to find a way to introduce the muggle to the wizarding world without breaking any rules.
The original Harry Potter series is based on themes of love, friendship, and the co - existence of wizards and Muggles. In the 'Harry Potter kills Muggles' fanfiction, it completely goes against this by having Harry, who is a symbol of good in the original, become a murderer of Muggles. This is a huge deviation from the core values of the series.
Often, Harry's development is more complex. He has to deal with two different worlds, the muggle world where he was raised and the wizarding world he belongs to. This dual - world experience can make him more adaptable but also more conflicted. For example, he may love his muggle family in some ways but also feel a sense of betrayal when he realizes they've been trying to keep him from his true nature. His relationships with other characters, like Hermione and Ron, may also be different as he has this unique background.
The 'him' could be Draco Malfoy. It would create an interesting dynamic as they are usually rivals. Maybe in a situation where they are forced to work together on a secret mission for the wizarding world, and they end up in close quarters, rubbing against each other accidentally. This could lead to a change in their relationship, from enmity to a more complex understanding.