In this fanfiction, it could be that Nightmare Moon has learned from her previous defeats. She could form alliances with other villains or corrupted creatures to increase her chances of success. Maybe she even tries to manipulate the elements of harmony in a new and devious way.
It's possible that the ponies are more prepared this time around. They could have developed new defenses or magical abilities. However, Nightmare Moon's third return might also bring out some hidden secrets or past traumas among the ponies that they have to deal with in order to defeat her once and for all.
Well, perhaps she comes back more powerful than ever. She might have new dark magic at her disposal and target different parts of Equestria this time.
There could also be some new characters introduced in the fanfiction. Maybe a mysterious unicorn with ancient knowledge about Nightmare Moon's origins. Or a group of creatures that have been affected by Nightmare Moon's previous reigns and are now seeking revenge or redemption by helping the ponies stop her third return.
In this fanfiction, Greninja might come back with new powers. Maybe it has been on a special training journey and returns to Ash to help him in a big battle.
In this fanfiction scenario, Ron could draw on his knowledge of the wizarding world. He might remember some ancient spells or potions that could safeguard Hermione. He'd be really determined to protect her. He could also call on his friends like Harry for help if the situation got really tough.
In this fanfiction, the Naruto family might be welcomed back with great joy. The villagers could hold a big celebration to honor their return. Naruto, as a hero, would finally be home with his family in Konoha, and his kids might start exploring the village that their father has so many memories of.
Well, he might go back to Hogwarts to search for some long - lost magic artifacts. It could be that there are secrets hidden in the castle that only he can uncover. And along the way, he could meet some old friends and have new adventures together. He might also find a way to further improve the security of Hogwarts after all the battles it has endured.
In this fanfiction, Ash might introduce Greninja to his family. His mother could be surprised but also happy to see such a unique Pokémon. Maybe Greninja would show off some of its cool moves in the backyard.
In this fanfiction, Naruto might finally have an emotional reunion with his parents. He could share all his adventures, growth, and the pain he endured. They would likely be proud of how he became a great ninja.
In this fanfiction, Naruto might reunite with his old friends and sensei. He could show off new jutsus he learned during his time away. Maybe he'd also face new threats to his realm that only he can defeat with his unique skills and experiences.
Well, in this fanfiction, Kagura might be welcomed back with mixed emotions. Some might be overjoyed to see her return, while others could be suspicious of her motives. Maybe she brings back new jutsu or knowledge from her time away.
Well, he might be greeted with both joy and shock. His friends would be overjoyed to see him alive again. Maybe he'll immediately start working on new tech to protect the Earth better this time.