Dragons are grouped by what is known as a potency, a classification based on what kind of energy they are defined by. Different energies can create the same dragon (e.g. love resonance and dumaqu both create sapphire dragons, though the latter are a subspecies called jeweled dragons), and some energies can be used to create different dragons even though it's the same energy (e.g. blood energy can create crimson dragons, opal dragons, and more). These potencies are similar to nations among dragons, as a group of dragons in an area with a significant amount of a specific energy will see many dragons of that kind form there.
Potencies:
Infernal Potency: Malaerian