Basilisks and Hydras were classified as beasts capable of producing High-level, Sage-grade Spirits, while Wyverns and Quetzalcoatls were classified as Low-level Primordial-grade Spirits. They were the first creatures of this quality that Liam had read about, inferior only to Dragons, which were supposed to produce Arcane Crystals and Spirits of the High-level, Primordial-grade.
According to {Dragons and Their Descendants}, even though it was almost impossible to find a Spirit Master with a Dragon's Spirit, finding an Arcane Crystal from a Dragon was something that could be achieved with a lot of effort and courage. Not only that, absorbing such a crystal could turn an ordinary Spirit Master into a renowned expert in just a few years!
