The primary protagonist of the Percy Jackson & the Olympians series and a child of the Big Three. As the favored son of Poseidon, Percy possesses immense hydrokinetic powers, allowing him to control water, speak to marine life, and summon sea storms. Marked by his messy dark hair and sea-green eyes that shift like ocean currents, he is fiercely loyal to his friends—a quality that serves as his fatal flaw. Recognized as a core leader at Camp Half-Blood, Percy later falls in love with Annabeth Chase, becoming her boyfriend.

The head counselor of Athena’s cabin and one of Camp Half-Blood's sharpest strategists. Annabeth has long dreamed of becoming an architect, driven by a desire to build monuments that last forever. She features athletic, blonde hair, a lean physique, and intense, stormy grey eyes that seem to analyze everything. Characterized by her incredible intellect, pride, and unwavering loyalty, she stands as a powerful demigod warrior and the longtime girlfriend of Percy Jackson.

Percy’s loyal best friend and a dedicated satyr who eventually rises to become a member and leader of the Council of Cloven Elders. Grover is easily recognized by his curly brown hair, small goat horns tucked under a rasta cap, brown furred caprine legs, and dark skin. His gentle demeanor is fueled by a love for nature, pan pipes, and an endless appetite for burritos (and aluminum cans). He plays a crucial role in finding lost demigods and bringing peace to the wild.

The venerable activities director at Camp Half-Blood, Chiron is an immortal centaur who has spent millennia training history's greatest heroes. Renowned for his vast wisdom, patience, and kind demeanor, he is extremely slow to anger and serves as a father figure to struggling demigods. When in the mortal world or presenting himself to unsuspecting humans, Chiron hides his equine lower half inside a magical, customized wheelchair.

A powerful son of Jupiter and a revered Praetor of Camp Jupiter. Viewed as a natural-born hero, Jason is admired by almost every Roman demigod for his noble heart and steady leadership. He is distinguished by his blonde hair, sharp blue eyes, a small scar on his lip, and his ability to summon lightning and ride the winds. Throughout his journey, he forms a deep bond with Piper McLean, becoming her dedicated boyfriend.

The energetic head counselor of the Hephaestus cabin, Leo is a brilliant machinist with the extremely rare, innate ability to generate and manipulate fire. Beneath his quick jokes, witty humor, and hyperactive nature lies a deep resilience. Leo has a short stature, curly brown hair, dark brown eyes, and a constant oil stain on his clothes. He carries a magic toolbelt and possesses an absolute passion for inventing and building mechanical marvels like Festus the dragon.

The head counselor of the Aphrodite cabin who defies the traditional stereotypes of her mother's children. Piper possesses the rare power of charmspeak, allowing her to persuade others to follow her commands through vocal influence. She has multi-toned brown hair, kaleidoscope eyes, and olive skin. Naturally pretty, kind, and fiercely independent, she prefers down-to-earth strength over vanity and is the devoted girlfriend of Jason Grace.

A son of Mars with a complex heritage that traces back to ancient shapeshifters. Though Frank is a imposing kid with a large, muscular frame and dark hair, he possesses a soft-spoken, gentle heart. Through his family blessing, he can transform into virtually any animal at will, making him a versatile power on the battlefield. Overcoming his self-doubt, he becomes a brave leader and the loving boyfriend of Hazel Levesque.

A daughter of Pluto who was brought back from the Underworld to live a second life. Hazel has warm cinnamon-colored skin, voluminous curly brown hair, and striking amber eyes. Despite her smaller stature, she possesses incredible inner resilience and the ability to navigate underground spaces and summon precious metals from the earth. She is a compassionate, kind soul and the girlfriend of Frank Zhang.

A powerful son of Hades who earns the title of "Ghost King" after defeating the spirit of Minos and claiming command over the dead. Nico has pale skin, dark messy hair, intense dark eyes, and a somber, isolated presence. Having spent long periods isolated from others, he gradually opens up and finds genuine happiness alongside his boyfriend, Will Solace.