It would be really interesting. Hermione is extremely intelligent and well - studied. If she were Harry's master, she'd likely focus a great deal on his academic improvement in magic. She might have Harry reading every magic book she could get her hands on, and drilling him on spells and potions. Their relationship would change from friends to more of a teacher - student dynamic, but with their shared experiences, there would still be a strong bond of friendship underlying it all.
If Hermione was Harry's master in a fanfiction, she would be very strict. She'd probably make Harry do a lot of research before attempting any new spells or facing challenges. For example, when dealing with the Triwizard Tournament tasks, instead of just jumping in like he did in the original story, she'd have him study the history of the tasks, the magic involved, and possible solutions from old wizarding texts. This would change the whole course of the events in the tournament, and Harry would become more of a strategic wizard under her guidance.
Ron could become Harry's master in a rather different way. Since Ron has a good sense of humor, his teaching style might be more laid - back. He'd use his knowledge of the wizarding world, especially things like the secrets of the Weasley family's magic, to teach Harry. For example, he could show Harry some unique spells that the Weasleys have passed down. But he'd also be a bit clumsy as a master, which could lead to some comical situations in the fanfiction.
Well, it could be about Harry coming back to life in a new and unexpected way. Maybe he returns with even greater powers, being the Master of Death. He might use his newfound state to fix all the wrongs in the wizarding world, like finally getting rid of all the remaining Death Eaters once and for all.
It could be really interesting. Maybe the Master of Death abilities would allow Harry to survive the dangerous situations in the Stargate universe, like going through the stargates to unknown planets and facing alien threats. He could use his magic along with the technology in the Stargate world.
Well, it could be that Harry has complete control over death. He might be able to bring back the dead, or at least communicate with them freely. Maybe he uses this power to right the wrongs of the wizarding world, like resurrecting those who died unjustly during the war. He could also use it to gain ultimate knowledge, as death is often associated with hidden secrets in the wizarding lore.
In such a fanfiction, we might see Harry Potter's magic blend with the spiritual energy of 'Bleach'. The Deathly Hallows could have new interpretations in the 'Bleach' setting. For instance, the Invisibility Cloak could be seen as a form of spiritual concealment. And his mastery over death might make him a sort of enigma to the characters in 'Bleach'. He could also learn about the different levels of souls in 'Bleach' and how they compare to the concept of death in 'Harry Potter'.
First, Harry would need to prove himself. As the Master of Death, he has a certain aura about him. In Asgard, he could start by saving a village from a monster attack. His ability to speak with snakes (if he still has that Parseltongue ability) might come in handy when dealing with some of the more mysterious creatures in Asgard. He could also use his experience from the wizarding world's wars to strategize against Asgard's enemies. As he gains more and more respect, he becomes a hero, and the Asgardians might start to see him as a protector, like they do with Thor.
It might be a story where Harry Potter, as the Master of Death, is brought to the world of Loki due to some magical accident. There, he has to face Loki's schemes and the different challenges of the Asgardian world. He could use his knowledge of magic from the wizarding world to deal with Loki's illusions and trickery.
Well, in such a fanfiction, Harry Potter being the Master of Death would have some really interesting interactions with the Avengers. Imagine Iron Man being intrigued by Harry's magic and trying to figure out how to incorporate it into his suits. Harry, on the other hand, might be a bit overwhelmed by the high - tech world of the Avengers at first but would soon find ways to use his magic in combat alongside the superheroes. The Hulk could be a bit of a wild card, and Harry might need to use some calming spells around him.
It could be really wild. Harry, with his power as the Master of Death, might disrupt the power balance in True Blood's vampire - werewolf - human world. Maybe he would use his invisibility cloak to spy on the vampires of True Blood. Or his ability to control death could have a huge impact on the vampires' immortality concept.
It could be really interesting. Maybe Harry could use his magic skills, like being able to Apparate, in Gotham City. He might team up with Batman to fight against some super - evil villains that are a mix of the magical and non - magical worlds. For example, Voldemort could somehow team up with a Gotham super - criminal, and Harry and Batman would have to combine their wits and powers to stop them.