Nico di Angelo could be a main character as well. His powers over the dead and his unique perspective could be valuable. He might be dealing with the influx of new ghosts due to the large number of casualties in the war and trying to find a way to give them peace.
Another option could be a new demigod. A character who was not very involved in the war but is now thrust into the post - war chaos. This new character could bring a fresh perspective and could be learning about the demigod world and its history while also trying to help in the rebuilding and healing process.
It could be some remaining monsters that survived the giant war and are now seeking revenge. They might target Nico specifically because of his role in the war. Another possibility is some rogue demigods who didn't like the outcome of the war and blame Nico for it.
There's a possibility that it's a new character introduced in the fanfiction. This new character could be someone who has a connection to the events of the giant war, like a relative of a fallen hero. They might be exploring the post - war world, uncovering secrets that were hidden during the war, and their journey could be the main focus of the story.
Well, George Weasley could be a main character. After losing Fred, he could be trying to keep the joke shop going while also dealing with his grief in a post - war world. Cho Chang might be another main character. She could be working with international wizards to strengthen relations between different wizarding communities after the war. And Seamus Finnigan could be part of the group. He could be involved in some magical research related to how to prevent future dark wizards from rising, using his experiences from fighting in the war.
One possible plotline could be about the rebuilding of the world. The characters might focus on restoring the damaged areas, re - establishing communities, and dealing with the aftermath of the destruction. For example, they could be working on rebuilding Camp Half - Blood and making it more secure against future threats.
It could be a rogue demigod who was on the losing side of the Giant War and is now seeking revenge. This demigod might have found some dark power or be allied with some minor but dangerous mythical creatures.
I think Nico di Angelo could also be a central character. He has his own unique powers and backstory, and after the giant war, he might be involved in some of the darker or more mysterious aspects of the post - war world, like dealing with any remnants of the Underworld's connection to the giants' plans.
Obviously, Team RWBY could be the main characters. Ruby could be the pilot or the one in charge of the mech's main weaponry. Weiss could handle the mech's ice - based defense systems. Blake could be in charge of stealth operations using the mech's cloaking features if it has any, and Yang could power up the mech's strength - related functions.
There could be new demigods. Maybe some who were hidden during the giant war and now come out. For example, a demigod of a less - known god or goddess.
Obviously, Sasuke and Sakura are the main characters. Sasuke with his complex past and new - found purpose after the war, and Sakura, who has always had feelings for Sasuke. In the fanfic, they are likely to be portrayed dealing with various post - war situations, like rebuilding the village, and their relationship is central to the story. They are the ones the readers will be most focused on as the story progresses.