Across
- 1. The Underworld river upon which gods swear unbreakable oaths.
- 4. Stylish ferryman of the Underworld who demands payment to cross the River Styx.
- 7. Goddess who inherited the moon chariot.
- 9. Ancient Titan sun god who appears in The Titan’s Curse driving the blazing sun chariot.
- 10. Son of Daedalus who fell to his death after flying too close to the sun.
- 12. Three immortal sisters who knit, measure, and cut the thread of mortal life.
- 14. Goddess whose appearance changes depending on who you like.
- 16. Son of Zeus and Hera who appears in the first book.
- 17. Queen of the gods who often interferes in hero quests for her own long-term plans.
- 18. Creator of the Labyrinth who hides himself using multiple identities in the series.
- 19. Goddess who quietly tends the fire at camp half blood and mount Olympus.
Down
- 2. The deepest, darkest pit of the Underworld—both a place and a living entity.
- 3. God of the Dead and father of Nico di Angelo.
- 5. Nature spirit such as a dryad or naiads, commonly encountered at Camp Half-Blood.
- 6. Multi-headed serpent Percy battles in The Lightning Thief at Waterland.
- 8. Sicilian volcano where Percy battles monsters and where Hephaestus’s influence is strongly felt.
- 11. Nico’s sister who joins the Hunters of Artemis in The Titan’s Curse.
- 13. Paradise within the Underworld where heroic souls earn eternal peace.
- 15. Ancient site of the Oracle whose spirit later inhabits Rachel Elizabeth Dare.
- 20. Magical food that heals demigods but burns mortals if consumed.