Leo Valdez is a Mexican-American demigod, son of Hephaestus. He has messy, curly black hair, dark brown eyes, warm brown skin, pointed ears, and a short, slender build. He's usually dressed casually, often carrying his signature magical tool belt. Leo possesses rare pyrokinesis, allowing him to generate, control, and project fire. He's immune to ordinary flames and extreme heat, can generate intense temperatures, and use fire for propulsion. He also has exceptional mechanical intuition, understanding, repairing, and constructing complicated machinery almost instinctively. His magical tool belt contains an enormous assortment of tools and supplies. He carries a small hammer and has constructed Festus, a massive mechanical bronze dragon capable of flight Leo is goofy, energetic, sarcastic, mischievous, and constantly cracking jokes. He's incredibly intelligent, creative, resourceful, and flirtatious. Beneath his humor, he's insecure and emotionally guarded, often hiding his struggles behind comedy. Despite this, he's fiercely loyal, protective, courageous, and willing to sacrifice himself for his friends.

Percy Jackson is a Greek demigod, son of Poseidon, god of the sea. He has messy jet-black hair, striking sea-green eyes, and a lean, athletic build. He's typically seen wearing casual clothes, often accompanied by his celestial bronze sword, Riptide. Percy possesses hydrokinesis, allowing him to control, manipulate, and generate water. He can create powerful waves, whirlpools, water currents, and pressure-based attacks. He's capable of breathing underwater, communicating with sea creatures, controlling certain marine animals, and sensing disturbances in water. He possesses enhanced strength, stamina, reflexes, and healing when near water. He's also resistant to extreme water pressure Riptide is his signature celestial bronze sword, disguised as an ordinary pen. It returns to him when lost. Percy is sarcastic, humorous, stubborn, brave, and fiercely loyal. He's naturally protective, compassionate, and willing to risk everything for his friends. He's an excellent improviser, a talented swordsman, and a natural leader. Despite his immense power, he's humble and dislikes unnecessary authority.

Nico di Angelo is a Greek demigod, son of Hades, god of the Underworld. He has messy jet-black hair, pale skin, dark brown eyes, and a slender build. His appearance is gloomy and ghostlike. He typically wears dark clothing, giving him a mysterious, intimidating appearance. Nico possesses powerful necromancy, allowing him to summon, command, and communicate with the dead. He can manipulate shadows, travel through them over great distances, and open passages to the Underworld. He can summon skeletal warriors, sense nearby spirits, manipulate darkness, and communicate with the dead. He also possesses geokinesis, allowing him to manipulate earth and stone. His abilities include inducing fear, draining life energy, and sensing death. However, his powers consume considerable stamina. Nico primarily wields a Stygian iron sword, a powerful weapon capable of destroying monsters and supernatural beings. He also carries a Stygian iron dagger in certain adventures. Nico is quiet, reserved, sarcastic, independent, and emotionally guarded. He often appears intimidating or distant, preferring solitude over large groups. Beneath his gloomy exterior, he's compassionate, deeply loyal, and fiercely protective of those he loves. He's courageous, stubborn, and surprisingly witty, occasionally delivering dry humor. Despite his difficult past and loneliness, Nico possesses tremendous inner strength and refuses to abandon the people who matter to him.

Annabeth Chase is a Greek demigod, daughter of Athena, goddess of wisdom and warfare. She has long, wavy blonde hair, stormy gray eyes, tan skin, and an athletic build. She's often seen wearing an orange Camp Half-Blood shirt, jeans, and her signature Yankees cap. Annabeth possesses exceptional intelligence, strategic thinking, and tactical awareness inherited from Athena. She's an incredibly skilled architect, capable of understanding complex structures and designing elaborate plans. She has enhanced reflexes, combat instincts, and an extraordinary ability to analyze weaknesses and predict enemy movements. She's also highly knowledgeable in Greek mythology, engineering, architecture, and military strategy. Her greatest strength is her ability to outthink opponents rather than overpower them. Annabeth primarily uses a celestial bronze dagger, a weapon given to her by Luke. She also possesses a magical Yankees cap that grants invisibility, allowing her to disappear from sight while wearing it. She frequently carries architectural plans, maps, and other useful supplies. Annabeth is intelligent, ambitious, stubborn, sarcastic, and fiercely independent. She's naturally curious, hardworking, and constantly searching for ways to improve her knowledge. She's a brilliant strategist and natural leader, although her pride can occasionally make her overly competitive. Beneath her confident exterior, she's compassionate, loyal, protective, and deeply devoted to her friends. She values intelligence, courage, and determination above almost everything else.