Drakons (not to be confused with Dragons) are giant, monster serpent-like creatures several millennia older than dragons. They were first mentioned in The Sea of Monsters and are later seen in The Battle of the Labyrinth, The Last Olympian, The Demigod Diaries and The House of Hades.
One drakon mentioned in the myths was of Sosipolis, a son of Eileithyia, the Goddess of Childbirth. As he was protecting the city of Elis as a child from the Arcadians, he transformed into a Drakon, causing the Arcadians to flee in terror. After this victory, he became the patron and defender of the Eleans.
Luke Castellan sent Percy Jackson, Annabeth Chase, and Tyson to be eaten by a drakon that was on his ship, the Princess Andromeda. He later threatened to have Agrius fed to it after learning that the Golden Fleece had slipped through his grasp.
A Lydian drakon was sent by Kronos to defeat the demigod forces protecting Mount Olympus. This drakon could only be killed by a child of Ares, but because the Ares cabin had refused to fight, the drakon ploughed through the Olympian forces and killed a large number of centaurs. It wasn't until Silena Beauregard was killed after charging the drakon in Clarisse La Rue's armour that the Ares cabin joined the fight. Clarisse charged the drakon in a vengeful rage without any armour and only her spear as a weapon and kills the drakon in the Battle of Manhattan before she received the Blessing of Ares.
Percy Jackson, Annabeth Chase, and Bob encounter the Maeonian drakon in a swamp in Tartarus. When it is about to kill them, Damasen appears and slays it. It is told that Damasen was cursed and his curse was to slay the drakon everyday in Tartarus. In Damasen's hut, Percy, Annabeth and Bob eat the meat of the drakon and Damasen gives Annabeth a drakon-bone sword. Later, Damasen appears after apparently having tamed the drakon and rides the drakon to battle against the physical form of his father, Tartarus.
- Some breathe fire, though most don't.
- Some spit acidic venom.
- All have extremely hard plate-like scales on their skin.
- Most can paralyze you with their eyes.
- Extremely hard to kill (the Lydian drakon was able to withstand several javelins to the mouth).