The Dragon is the subject of an oath ("By the Dragon,...") used by "Iago", Angel, and Hudson. The exact nature of the Dragon is as yet unknown (though all of them were once members of the Wyvern Clan, and a wyvern is a two-legged dragon). ("Possession", "Tyrants", "Render Unto Caesar")
When the Commandos depart from Castle Wyvern, Hudson thinks at first that their helicopter is a dragon, before Lexington identifies it to be a machine. Even years later, he still thinks of helicopters as "modern day dragons". ("Awakening: Part Two", "The Reach")
It is uncertain as yet as to whether genuine dragons exist in the Gargoyles Universe, beyond the magically animated stone statue that King Arthur, Griff, and Macbeth battled in the Brooklyn Botanical Gardens.