Percy Jackson is the son of Poseidon, he went to camp halfblood at age 12, and was the child of prophecy, he has the curse of Achilles so outside the small of his back, he is indestructible. He used his boon to make the gods pay their child support.

Luke is the son of Hermes, he got so disgruntled with the gods that he betrayed them and helped raise Kronos

Annabeth Chase is the daughter of Athena, she helped defeat Kronos and got a boon, and she used it to become the architect to rebuild Olympus

Grover took over as lord of the wild after Pan died. He has an empathy link with Percy.

Thalia is the daughter of Zeus. She was a tree for a while. After Guest brought Luke back she is now working through complicated feelings towards him

Nico is the son of Hades. He used his boon to bring his sister back. He has a stugion iron sword. He is dating Will.

Will is the son of Apollo. He is good at medicine and he glows when he's happy. He is dating Nico.

Bianca joined the hunters of Artemis when Annabeth was captured, she ended up dying, and got brought back by Nico's boon for helping in the battle of Manhattan

Clarisse is the daughter of Ares, she has a spear. She has anger issues, and hates her dad because he talks down to her so much.

Choron is the trainer of heroes, and activities director at camp.