One interesting scenario could be the Hogwarts Express traveling to far - flung magical locations in Asia. Maybe it stops at a hidden magical village in the Himalayas where they have unique spells and potions. Another could be it going across the Americas and encountering magical creatures that are native to those regions, like the Thunderbird in North America.
In 'Harry Potter train around the world' fanfiction, there could be a scenario where the train is hijacked by dark wizards while on its journey. The students and staff on board then have to use their magic and wits to fight back. This could lead to some really intense battles and character development. It could also be that the train travels to the Arctic regions and uncovers a magical mystery related to ice and snow magic.
In such fanfictions, one interesting scenario could be Harry Potter visiting the Great Wall of China. He might use his magic to explore the hidden parts of the wall that are not accessible to Muggles. Another could be his visit to the Amazon rainforest, where he discovers magical creatures unique to that area and has to use his skills to protect them from dark wizards who want to exploit their magic.
Most likely, Harry Potter himself would be one of the main characters. He has a natural inclination for adventure and would be eager to explore the world on the train. Hermione Granger would also be there, with her vast knowledge of magic to help them out in different situations. Ron Weasley too, for his loyalty and friendship.
In certain 'Harry Potter travels to other world fanfiction', Harry could end up in a world where magic is used in a more primitive way. He may find that the wizards there use potions made from rare plants that don't exist in his world. And he has to use his skills to figure out how to communicate with these wizards, as their language of magic is different. He might also discover new forms of magical transportation, like floating stones that can carry people across great distances.
One interesting scenario could be that it's a moment of extreme relief. Maybe they've just survived a dangerous encounter at Hogwarts and as they're on the train leaving, the emotions are so high that they share a kiss. It's a spontaneous act, out of the joy of being alive and having each other's support.
One interesting scenario could be shopping for magical pets in Diagon Alley. In some fanfictions, characters might discover rare and unique creatures that are not typically found in the original books. For example, a magical hybrid of a phoenix and a cat that can both fly and purr.
Well, there are dueling scenarios where characters from different generations meet in a magical duel. For example, a character from Harry's time might accidentally travel back and duel with a student from the Marauders' era. This can lead to some really creative uses of magic as they try to outwit each other with different spells and strategies they've learned in their respective times.
One interesting scenario could be an OC who is a muggle - born wizard but has unique magical abilities not seen in regular wizards. For example, they might be able to communicate with magical creatures in a way that no one else can.
A common boggart scenario in fanfiction is related to the characters' insecurities. For Harry, it could be that the boggart shows him as the cause of all his friends' misfortunes, emphasizing his fear of being a burden or a danger to those he loves. This can add more depth to his character and explore his self - doubts further.
One interesting scenario could be when the characters are in detention and they discover a hidden magical object. For example, in some fanfictions, Harry and his friends might find an old, enchanted diary during detention in the castle. This diary could hold secrets or be a portal to another time or place.
One interesting 'last will' scenario could be a character leaving behind a powerful magical artifact in their will. For example, a wizard might leave a wand with special properties to Harry Potter, which could be a key to defeating a new dark force. This would add an extra layer of mystery and power to the story.