Dragons, also referred to as Gatekeepers and Ancient Ones, are primordial reptilian creatures of immense arcane knowledge.
- "Great mages have wasted their lives trying to get at the root of magic. It is a futile pursuit, not much fun and occasionally quite hazardous. Because the farther down you go, the bigger and scalier the turtles get, with sharper and sharper beaks. Until eventually, they start looking less like turtles and more like dragons."
As explained by Professor March, whenever Magicians throughout history attempted to research the origins of magic, their search would become more hazardous before it eventually lead them to face a dragon. Eliot Waugh considered talking to the Thames Dragon for career advice after he graduated from Brakebills University, stating the dragon was a better option than the dragons of the Ganges, Mississippi, and Neva rivers.
When trying to get back to Fillory, Quentin Coldwater spoke with the Grand Canal Dragon in Venice, who purchased the button Coldwater previously used from Josh Hoberman. Later, while traveling through the Neitherlands, Coldwater caught a glimpse of Mischa Mayakovsky riding on the back of a large white dragon as he battled against the Old Gods.
In the 40th timeline, while searching for a way to travel to the Underworld, Quentin Coldwater and Julia Wicker discovered that they would need to find a dragon to access the land of the dead. The two later visited the nest of the Hudson River Dragon in New York City, who offered passage in exchange for the enchanted button Coldwater used to travel to Fillory.
After escaping the attack on her classmates by The Beast, Poppy Kline spent some time traveling the Eastern Ocean in Fillory when she and her crew discovered a dragon breeding ground on an island, where she stole a golden key before leaving. After giving the key to Coldwater, Kline revealed that it conjured an illusion that drove her crewmates to suicide, and Coldwater decided to keep it safe on him until they returned to Castle Whitespire. However, Benedict Fenwick came into contact with the key and jumped into the water of the Abyss, where he was eaten by the Abyss Dragon waiting in the water below. When Coldwater learned that the key was transported to the Underworld, he and Penny Adiyodi orchestrated a plan to retrieve the key using the Bookwyrm, the Library's dragon, to send the key to the Satellite Library.
When the god Nameless possessed the body of Eliot Waugh, Coldwater and his friends agreed to help him recover several Stone Organs to restore his body. With the help of Kady Orloff-Diaz, Coldwater and Wicker learned that the East River Dragon was in possession of one of the god's organs, and after helping the dragon find the thief who stole her elixir, the dragon send her herald to deliver the organ to Wicker, in addition to relaying a message telling Wicker to find the Binder to help her regain her divinity.
The draco-reproductive process is similar to aquatic animals: females produce eggs that remain unfertilized, in or outside the womb, until seeded by males. Cross-breed reproduction is possible, though it's uncertain if it results in hybridization. Dragon eggs take three years to gestate after fertilization and release a magical pheromone that instills a powerful nesting instinct to any who come in contact with it. Eggs also require a hospitable environment consisting of extreme heat, proximity to sand (or other quartz-based minerals), and constant affection.
Noted as being practically immortal creatures, dragons have extremely long lifespans. The Grand Canal Dragon has lived in Venice for over ten centuries, and the East River Dragon is over 12,000 years old, which she stated was too young for a dragon to have children. Dragons are also extremely large, able to swallow humans whole, with their heads being described as the size of a compact car. Some breeds, however, are smaller than humans; the Bookwyrm, an Albanian pygmy, is used by the Order of the Library of the Neitherlands to send books to the Underworld due to it's smaller size. Their bodies are covered in scales that are approximately as thick as encyclopedia volumes, and some carve sigils and pictograms into them. Their voices resonate very deeply, almost sub-bass like, while smoke is sometimes produced when they speak verbally.
Most dragons are water dragons, solitary creatures who rarely break the surface to speak and spend most of their time asleep at the bottom of their rivers. Although dragons have their own names, they’re impossible to pronounce for others so they are named after the river they dwell in. Dragons are highly territorial, as only one dragon can be found in each of the world’s major rivers, and they are known to collect valuable objects to use for their nests which are kept well-maintained and undisturbed by pollutants and trash.
Well respected for their intelligence, dragons are often approached by Magicians for their advice or insight into the origins of magic. Despite this, they usually spend their time slumbering and will often only talk with Magicians to play games. They can also sense powerful magic, as the Hudson River Dragon was able to sense the enchanted button in Quentin Coldwater’s pocket. Dragons have breeding grounds, though they are incredibly rare to find, and only two breeds actually build nests out of treasure they collect.
Dragons are known as Gatekeepers due to their ability to open portals, as well as the fact that anything a dragon ingests gets transported to the Underworld, including the souls of people they eat. They can also grant passage to the Underworld by separating others' souls from their physical form. According to Poppy Kline, dragons only ever eat humans twice a century.
Dragons are stated to live in rivers all over the world and are typically named after the river they dwell in. The known, or otherwise identified, Dragons include:
- Thames River Dragon
- Ganges River Dragon
- Mississippi River Dragon
- Neva River Dragon
- Antarctica Dragon
- Grand Canal Dragon
- Hudson River Dragon
- Abyss Dragon
- East River Dragon
- Seine River Dragon