Dragons are huge ancient creatures that have a large variation and a very impressive evolutionary line. Though there's a lot of variation among different kinds of dragons.
The Thornback dragon is well known for the spikes on it's spine. This kind of dragon likes tall high heights. The Thornback dragon is usually aggressive of the dragon kind. This dragon can exhale fire, like many dragon variations.
The Thorntail dragon is known for the spikes in it's tail. A Thorntail will swing their tail at enemies of any sort, or if they are taunted too much. They will also raise their tail as a warning. In short, Throntails have a toleration limit, but if that's broken, they will likely bring harm to the agitator and those around the individual. Gynoss's first dragon, Dracco, is a Thorntail Dragon. A Thorntail also breathes fire for the most part, though if they get into a rage, they might exhale lava as well.