Who are the potential allies or enemies Percy could meet in a 'Percy in Tartarus alone' fanfiction?

Bob the Titan could potentially be an ally. Since he has some knowledge of Tartarus and has shown kindness before, he might come to Percy's aid again. He could help Percy navigate the dangerous areas and avoid some of the more powerful threats in Tartarus.

There might also be a lost spirit or a demigod who was previously trapped in Tartarus and has managed to survive. This character could share their experiences and skills with Percy, and together they could try to find a way out or at least make the best of their situation in Tartarus.

There's a chance that Percy meets the personification of Tartarus itself. It could be a shadowy, all - powerful being that tries to break Percy's spirit. Percy, being the brave hero he is, would have to resist and find a way to either outwit or overpower this entity in order to continue his journey in Tartarus.

He could find some minor gods or goddesses who have been banished to Tartarus. They might see Percy as a way to get revenge on the Olympians or simply a means to escape. Another potential ally could be some of the more intelligent monsters, like a centaur who has been there for a long time and has knowledge of the place.

Grover could also be an ally. His connection to nature might give Percy some unique advantages in Tartarus. Additionally, some of the less hostile creatures in Tartarus, like the friendly Cyclopes, could side with Percy. They might see him as a more just ruler compared to the chaos that usually reigns in Tartarus. Also, Chiron, with his vast knowledge and experience, could offer guidance from afar, which could be considered a form of alliance.

Annabeth would definitely be one of his top allies. She's been with Percy through many adventures and her intelligence would be crucial in helping Percy understand his connection to the creator and any new situations that arise. For example, she could research ancient texts to find clues about the creator's intentions for Percy.

Frank Zhang could also be an ally. He is a Roman demigod with shape - shifting abilities. His strength and loyalty would make him a valuable teammate for Percy. Additionally, Nico di Angelo, who has ties to both the Greek and Roman worlds, could be an important ally. His knowledge of the Underworld and his ability to shadow - travel could help Percy in various situations, whether it's getting information or quickly moving around in the Roman camp.

Nico di Angelo could be a great ally. Since he has his own connection to the Underworld, he might understand Percy's new situation better. Another could be Thalia, as she's always been a strong and loyal friend. She would likely stand by Percy despite his new dark powers. Also, Grover could be an ally. His empathy and loyalty would make him support Percy no matter what.

Annabeth could be a strong ally. She's smart and has always been by Percy's side. Her knowledge and strategic thinking would be invaluable when Percy is dealing with the new aspects of his primordial powers.

Grover might also be an ally. His connection to nature could be useful in Percy's new role. For example, he could help Percy understand any nature - related aspects of Olympus or deal with nature spirits in the realm. Also, some of the more benevolent gods like Poseidon (Percy's father) and Athena (Annabeth's mother) might side with Percy, at least to some extent, as they have their own interests in seeing Percy succeed in maintaining order in Olympus.