Well, perhaps in this fanfic, Emiya has to face some moral dilemmas during the fourth war. He might be forced to make choices between saving civilians and achieving his goals in the war. Also, his relationship with his Master could be explored in a new light. What if his Master has a hidden agenda that conflicts with Emiya's own sense of justice? That would surely add a lot of drama to the story.
Well, Saber is often a key figure in Holy Grail War stories. In this fanfic, she could be involved in some way with Emiya. Maybe they cross paths and have to decide whether to fight or cooperate. Additionally, Gilgamesh might make an appearance. His over - the - top personality and powerful abilities would surely create some interesting dynamics when interacting with Emiya.
One idea could be exploring Archer's internal struggle more deeply. Maybe show his memories of past battles and how they affect his decisions in the Fourth War. Another could be to create a scenario where Archer has to team up with an unexpected character from the Fate universe.
The relationships between the characters can also be an interesting concept. In the fanfic, characters who may not have interacted much in the original could form strong alliances or rivalries. It can show how different personalities clash or complement each other in unexpected ways.
A possible plotline is a love triangle situation. Maybe both Archer and Emiya develop feelings for Saber. This could lead to a lot of tension and drama between them. Saber, on the other hand, is focused on her own goals but can't help being affected by their affections. There would be emotional confrontations and decisions to be made, which could add depth to their relationships.
The Emiya ending in the Fourth Grail War fanfiction often shows his complex character. He is a hero with a strong sense of justice. In this ending, he might face difficult choices. Maybe he sacrifices himself to save others, which is in line with his selfless nature.
One key element is Emiya's determination. His unwavering will to do what's right is a big part of the ending. He won't be swayed by the temptations of the Grail. Another element is his relationships. His connection with other characters, like how he helps or is helped by them, can greatly affect the ending.
Another plot idea might be to focus on Shirou's internal struggle during the Grail War in more depth. Show how his ideals are tested not just in battle, but also in his interactions with other Masters and Servants. Maybe he has to make some really tough moral choices that could change the course of the war.
One interesting plotline could be about the different factions in Equestria warring over scarce resources. For example, the ponies of Canterlot might be fighting with the ponies from Ponyville due to a shortage of magic crystals. Another could be a story where an unlikely hero emerges from a small group of ponies who were previously overlooked in the war effort. Maybe a group of earth ponies discovers a new way to defend their land against the more magically - inclined opponents.
One interesting plotline could be Shirou using his gamer skills to quickly analyze and defeat opponents in the Holy Grail War. For example, he might see the battle scenarios as levels in a game and use strategies he learned from gaming to outwit his enemies. Another could be him leveling up his own abilities in a way similar to how a gamer levels up a character, perhaps unlocking hidden powers within himself that were previously unknown.
One interesting plotline could be Sasuke and Sakura exploring their new relationship in a post - war world filled with rebuilding. They might face challenges in their relationship due to the traumas of war. Another could be them working together to heal the wounds of the village, both physically and emotionally. Maybe they discover new aspects of each other as they do so.