All dragons, on all planes, are descended from the Ur-Dragon, the Progenitor of Fire and the avatar of all dragonkind itself. As such, there's been a lot of them, and they regularly show in places where you wouldn't normally expect them but with some concessions to the set's tone, such as the Gothic Horror plane of Innistrad, which gets dragons with wings like stained glass, or the crocodile-headed dragons of the Egyptian Mythology-inspired plane of Amonkhet.
Magic: The Gathering: Dragons are the iconic creatures (that is, a large, powerful creature that shows up as a rare card once a set) of Red (the color of chaos, fire, mountains and raw emotion), although they've showed up in all other colors with less frequency.
