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Noble dragons (Draco nobilis) are intelligent, arrogant, powerful, and graceful and beautiful in a specialized sense. Noble dragons are huge and winged, can produce an extremely hot flame, and seem to defy normal physics in both their flying and their flaming. If they are flesh and blood, each noble dragon will weigh many tons, but the one noble dragon that appeared in Ankh-Morpork lazily flaps its wings once to take off, and glides around for the rest of the flight. The noble dragon doesn't seem to have eaten much in the way of energy-rich fuels, but its flame has been far hotter than that of the most gluttonous swamp dragons.

The fact is, the noble dragon is one of the Discworld species that has evolved to live on magic. Their body materializes by magic, they flame by magic, they fly (or glide) by magic. Since the large amount of magic required for a noble dragon to exist in the more normal dimensions of Discworld is not available everywhere, noble dragons have gone into another dimension, all metaphorically squished up like rather huge and beautiful sardines. A noble dragon is summoned by a person, or several people, performing a ritual according to The Summoning of Dragons written by the wizard Tubal de Malachite many years ago. People performing this ritual have to imagine the dragon very intensely, and gather objects that might be magical. The noble dragon feeds on the magic, comes through the mind of one of those people, and afterwards may become able to read his mind. In effect, the materialized noble dragon shares some personality traits of the performer of this ritual.

The beautiful but rather transparent dragons in Wyrmberg, back in The Colour of Magic, were possibly a mass-summoned population of noble dragons.