Another common opponent could be other demigods from different cabins. For instance, a child of Ares who might have a more aggressive and straightforward fighting style compared to Percy. This would create an interesting dynamic as they have different powers and personalities but are still on the same side in the general scheme of things.
One likely opponent is Luke Castellan. Since they have a complex relationship in the original series, it would be a very emotional and intense battle in fanfiction. Luke has his own set of skills and powers, and his motives would make the battle even more interesting.
Monsters from Greek mythology are also very common. Giants, like the ones Percy faced in the original series, are frequently used. They are powerful and require Percy to use his water - based powers in creative ways to take them down. It's a classic type of fight that fans love to read about.
Perhaps there could be a team of demigods from another camp. They see Percy as a threat on the soccer field and want to prove that their camp is better. They might use their own unique powers during the game in an attempt to outplay Percy. For example, a demigod from a fire - based camp could heat up the soccer ball to make it difficult for Percy to handle.
One common near - death scenario could be facing a powerful monster like a Hydra. The Hydra has multiple heads and can be extremely difficult to defeat. Percy might be caught off - guard by its regenerating heads and be on the verge of death. Another could be when he's in the Underworld and has to deal with the various deadly traps and hostile entities there. Maybe he gets poisoned by some underworldly plant or attacked by a horde of shades.
One opponent could be a child of Ares. Since Ares is the god of war in Greek mythology, his descendants would likely be fierce fighters. They would have a natural inclination towards combat and would be a great challenge for Percy. Another could be a monster in disguise. Maybe a minotaur that has learned to fight in the MMA style. It would be a very dangerous and unpredictable opponent for Percy.
His mother, Sally Jackson, could play an important role as an ally. She has a strong will and has always been there for Percy. Also, Tyson, his cyclops half - brother, could be a powerful ally with his strength and loyalty. And don't forget about the Nymphs. Some of the water nymphs might help Percy since he has a connection to water.
Percy Jackson himself is very common, as the main character of the original series. Writers often like to put him in new and chaotic situations.
Percy Jackson himself is obviously very popular. He's the main character in the original series and in many fanfictions, his growth and new adventures are central. Another popular character is Annabeth. Her intelligence and strategic thinking often play important roles in the battle - related fanfictions. Also, Ares, as the god of war, is often a key figure in these stories.
One interesting story could be where Percy uses his water powers in a very creative way during the Death Battle. Maybe he creates a huge water shield that not only blocks attacks but also reflects them back at his opponents.
Nico di Angelo has a strong connection to the Underworld, so he's a prime candidate. He can already communicate with the dead and has some control over the shadows, which are related to death in a way. In fanfiction, he could be further developed to become the Master of Death, perhaps by making a deal with Hades or finding a hidden power within himself.