The Title of Wyvern

Wyverns are a classification of animals whose species have a high amount of the wyvern aspect found within their ether. Once the concentration of this aspect, which permeates throughout its ether, reaches a certain threshold, that particular species can be classified as a wyvern.

Wyvern Aspect

While the sentient species can have aspects such as daemonic or seraphic, every other animal contains varying amounts of the wyverian aspect as a part of their etherious blueprint. Its been currently observed that the the concentration of an aspect seems to coincide with the pronunciation and strength said aspect's characteristics has on the species and even individual, this principle is the same for both humans and animals.

The intensity of the wyverian aspect correlates to the inherit strength and abilities of the creature, those with very minute traces of the aspect include creatures such as the humble dog or household cat. The wyverns that barely make it past the threshold are seen to be those who aren't that inherently dangerous or have especially deep traits.
Those with more are the wyverns that have more complex traits, biology and abilities.

Species with particularly higher amounts are the ones with very unique capabilities, and are often more innately powerful or pose more of a threat.
Though a species have a general range of concentration of wyvern aspect, on an individual basis some creatures can have very slightly higher or lower amounts than other members of its species, but that small amount can make quite a difference as those individuals with more are considered stronger or superior to their brethren in one way or another.

Esoterym Wyverns

Among those classified as wyverns, there exists the step beyond. Certain species have an extrodinary amount of the wyvern aspect within them, to the point where they have abilities that seem to surpass their biology and are more akin to etherious abilities. These rare species of wyverns are referred to as esoterym wyvern for their mysterious and powerful attributes, are often quite ancient, as there is a reason why they have lasted this long. Many esoterym have extrordinary powers which some even granted from the species' ability to control their own ether like sentient creatures, many are very intelligent, many are even treated sentient.

If they do have a soul in there, its quite difficult to identify. Nevertheless, nature must be respected, if they aren't, these wyverns certainly have the ability to force it.

Though the title of wyvern may bring to mind images of winged reptiles, they are certainly not limited to them as they may also be great fanged beasts, twisting leviathans, feathered foes, deadly insects, massive arachnids, anything between and everything beyond.