Percy is a modern-day demigod son of Poseidon. He serves as the narrator of the collection, injecting his signature humor and contemporary references into ancient myths. He aims to warn and educate other half-human children about the dangerous realities of the godly world by translating ancient texts into understandable, modern language.

Gaia is the first of the primordial gods, representing Earth itself. She often appears in human form as a matronly woman with a green dress and a serene smile. She exerts quiet control over the world, inciting the initial rebellion against her husband Ouranos out of anger over the imprisonment of her monstrous children.

Kronos is the youngest and most cunning of the Titans. Driven by ambition, he overthrows his father to become the lord of creation and rule over a violent Golden Age. Terrified of a curse predicting his downfall, he desperately swallows his own newborn children to prevent them from seizing his power.

Zeus is the king of the Olympian gods and lord of the sky. As the youngest son of Kronos and Rhea, he leads the charge to overthrow the Titans. He has a severe temper, a massive ego, and a habit of destroying mortals and punishing gods who defy his absolute authority.

Hera is the queen of the gods and goddess of motherhood. She has a short temper and fiercely guards her independence, taking offense at Zeus's constant affairs. Unable to strike at Zeus directly due to his power, she frequently exacts sneaky, cruel revenge on his mortal lovers.

Poseidon is the god of the sea and Percy Jackson's father. As the middle child, he maintains a laid-back attitude compared to Zeus and Hades, though his anger can sink islands. He builds a sprawling underwater palace and enjoys a relatively stable marriage, despite carrying on outside affairs.

Ouranos is the primordial god of the sky whose skin changes color from daylight blue to starry black at night. He cruelly imprisons his less desirable children in the deep pits of Tartarus, sparking a family conflict that results in his violent overthrow at the hands of his son Kronos.

Rhea is the Titan of motherhood and wife to Kronos. Horrified when her husband swallows her first five babies, she relies on her mother Gaia for a plan to save her final child, tricking Kronos into swallowing a rock instead.

Hestia is the firstborn Olympian goddess and protector of the hearth. Quiet, kind, and domestic, she avoids the dramatic conflicts of her siblings by refusing marriage and tending the central fire in the throne room on Mount Olympus.

Demeter is the goddess of grains and agriculture. Though lacking the raw destructive power of her brothers, she commands immense influence over the earth's food supply, willing to freeze the world and starve humans to force the other gods to return her kidnapped daughter.

Hades is the gloomy lord of the Underworld. Resentful of not having a throne on Mount Olympus, he focuses obsessively on organizing the domain of the dead and devising highly creative, eternal punishments for evil mortals.

Athena is the goddess of wisdom and warfare. Highly cunning and strategic, she frequently outsmarts other gods, especially Poseidon. She values martial skill but possesses a prideful dark side that surfaces when mortals challenge her superiority.

Aphrodite is the incredibly beautiful goddess of love. Vain, self-absorbed, and petty, she values appearances above all else and manipulates the emotions of both gods and mortals to ensure she remains the center of attention.

Ares is the brutish, aggressive god of war. Unpopular among the other Olympians due to his nasty personality, he serves as the patron for bullies and violent warriors, enforcing cruel punishments on those who cross him.

Hephaestus is the brilliant blacksmith god. Deformed from birth and rejected by his mother, he uses his unmatched crafting skills to build thrones, automatons, and clever traps to exact revenge on those who mistreat him.

Apollo is the handsome, arrogant god of archery, poetry, and the sun. While suave and deeply talented at music, his massive ego leads him to inflict horrific punishments on anyone who insults his skills or his family.

Artemis is the fiercely independent goddess of the hunt. She despises men and guards her followers closely. She operates by a strict moral code regarding nature, swiftly destroying humans who kill animals for sport rather than survival.

Hermes is the cunning god of travelers and thieves. As a trickster, he invents musical instruments to barter his way out of trouble and frequently handles dirty work and sneaky errands for Zeus.

Dionysus is the god of wine. Raised in secret among nymphs and satyrs, he gains vast power and a dedicated following by inventing wine, which brings joy to mortals but also incites chaotic, murderous madness when he is crossed.

Persephone is the beautiful daughter of Demeter. She is kidnapped by Hades and brought to the underworld, where she eventually adapts to her new life, though she remains caught in a restrictive custody arrangement between her mother and husband.

Prometheus is a Titan who creates humans and steals fire to give to them. He suffers endless daily torture chained to a rock by Zeus for his disobedience, enduring an eagle pecking out his liver every day.

Arachne is a talented mortal weaver who dares to create a textile depicting the gods' cruelest acts. Her challenge ends in a brutal beating that transforms her into the first spider, dooming her descendants to weave forever.