Since I don't know the exact story, it's hard to say. But likely there would be masters, who are the ones controlling the servants in the Holy Grail War. And then there would be the servants, who might have various heroic or mythical identities.
In this 'imperial capital holy grail war strange story', the main characters could include powerful mages as masters. They might be from noble families in the imperial capital, each with their own agendas. The servants could be drawn from different mythologies, like a valiant knight from Arthurian legend or a powerful god from Norse mythology. There could also be some side characters, perhaps a street urchin who stumbles upon the secrets of the war and gets involved in some way.
I'm not entirely sure specifically as it's not a common well - known story title. It could potentially be about a strange event or series of events that occur during a Holy Grail War set in an imperial capital. Maybe there are unique characters, magic, or power struggles involved.
Shirou is obviously a main character. Often, Saber would still be a major part as well, since she has a strong connection with Shirou in the original story. Other Servants and Masters from the original Holy Grail War concept might also appear.
There were a few novels that met this requirement, such as Sword Immortal who joined the chat group, Infinity from the Giants, and The Final War of the Apocalypse. The protagonists of these novels were involved in the Holy Grail War, but the main content of the novels was not the Holy Grail War. It involved different worlds and storylines. If you're interested in these novels, you can read them. I hope you like my recommendations.
In the Holy Grail original story, King Arthur is a main character. His court and the knights of the Round Table play important roles too. Sir Galahad is a key figure known for his pure heart in the search for the Grail. Sir Lancelot is also important, though his relationship with Queen Guinevere sometimes complicates his part in the Grail quest.
Archer is often very popular. His cool and somewhat aloof personality, along with his powerful abilities, make him a favorite. Saber is also a top pick. Her noble image and strong sense of justice are appealing. And Gilgamesh, with his over - the - top arrogance and incredible power, is frequently featured in fanfiction.
There were two novels that traveled to the Holy Grail War that could be recommended. The first book was Fate: The Reversal Axis. The story was about the descendant of the Devil Dao, Ying Dachu, who participated in the Holy Grail War in order to fight for the wishing machine. The second book was " Yuki's Journey to the Holy Grail." The protagonist Yuki participated in various Holy Grail Wars in order to return to Asuna's side. These two novels were both about traveling to the present world to participate in the Holy Grail War.
One could be a young female mage as the main character. She might be from a family that has been on the outskirts of the mage society and is trying to prove herself in the Grail War.
😋I recommend you a novel called Conan: The Correct Way to Make a Wish on the Holy Grail. In this novel, a Holy Grail vessel was reincarnated as the child of a fox demon after the Holy Grail War, and its identity became even more special. This Holy Grail also had an older brother and an uncle who was a cross-dressing boss. The life of the non-human Holy Grail was very rich and interesting. Every day, he enjoyed the love of many shikigami. I hope you like this fairy's recommendation. Muah ~😗
The main characters are King Arthur himself, of course. Then there are his knights like Sir Lancelot, Sir Galahad, and Sir Percival. Merlin, the wizard, also plays an important role in the story related to Arthur and the Holy Grail.
Servants are also often main characters. For instance, Saber, with her noble and powerful presence. In the fanfic, she might have different relationships with other characters compared to the original. Her backstory and her connection to the Grail War are important elements that make her a main character.