Maybe the house elves train Harry in the art of stealth. Since they are so good at moving around unnoticed in the wizarding world. They could pass on those skills to Harry, which would help him greatly in his battles against Voldemort and his Death Eaters. Harry could then use this new - found stealth to gather intelligence or surprise his enemies.
In this fanfiction, it might be that the house elves train Harry in their own form of magic which is more connected to nature and the very fabric of the wizarding world. They could introduce him to magic that is based on loyalty and servitude, but in a way that gives Harry more power. For instance, they might teach him spells that are powered by the strong bonds of friendship and loyalty, which could be a new source of strength for Harry against the dark forces.
Perhaps some of the pure - blood wizard families who look down on house elves training a wizard like Harry could be antagonists. They might see it as a threat to the traditional wizarding hierarchy and try to stop Harry and the house elves, thinking that it's not proper for a wizard of Harry's status to be trained by 'mere' house elves.
Perhaps Voldemort has cast a powerful spell on Harry that the normal wizarding community can't break. But the house elves, with their different kind of magic, are not affected in the same way. They detect Harry's plight and use their loyalty and cleverness. For example, they might create a magical shield around Harry that slowly weakens the dark spell, eventually saving him.
In a fanfiction where Harry Potter is trained by elves, it could lead to some interesting character developments. He might become more empathetic towards the elves' situation in the wizarding world. The training could involve a lot of physical and mental challenges that would make him stronger. For example, elves are known for their patience and discipline, and Harry could pick up these qualities. This would not only change his relationship with other characters like Hermione and Ron, but also his standing in the fight against Voldemort. He could use the skills and knowledge he gained from the elves to come up with new strategies and perhaps even find some weaknesses in Voldemort's magic that he wouldn't have noticed otherwise.
The story could change a great deal. His power level might increase significantly. Since elves have their own form of magic, Harry could combine it with his existing wizarding magic. This could make him a more formidable opponent against his enemies. For instance, he might be able to use elf - like stealth in battles.
Dobby would likely be one of the important house elves. He has shown great courage and a willingness to go against the norm to help Harry in the original series. In this fanfiction, he could be the leader among the house elves in the rescue mission.
Dobby is often very popular in fanfiction. Since he was already a well - developed character in the original series, fanfiction writers like to expand on his story further. He might be shown having more adventures or getting into different kinds of trouble. Another popular one is Kreacher. Writers may explore his complex personality more deeply, perhaps showing a side of him that was not fully explored in the books, like his loyalty to the Black family in new and interesting ways.
Well, it could be about Harry Potter being invited to the council of elves. Maybe they need his help to deal with a dark magic threat that is affecting the elven realm. Harry's unique skills and knowledge from Hogwarts could be put to good use in this elven adventure.
One possibility is that Harry discovers a world where fanfiction has the power to change the real wizarding world. So he has to train to fight against the alterations caused by these fictional stories. For example, if a fanfiction made Hogwarts a place full of dangerous magical beasts that don't belong there, Harry would need to train to restore order.
Well, perhaps Harry could be trained in some long - lost or dark magic that Dumbledore has been hiding from him. This new training might make him even more powerful than before, able to defeat Voldemort in a more spectacular way.
Maybe Harry discovers some long - lost magic techniques taught by Godric. He could become super powerful and use ancient spells to fight Voldemort.