Orphnoch are a Human evolutionary stage, usually created either when a Human dies or when they're sired by another Orphnoch. They are stronger, tougher, and faster than Humans, with various other special abilities.
There are two types of Orphnochs in the most of series: the Original Orphnochs who are "born" when a certain human suffers a death and 'resurrected' into an Orphnoch and Sired Orphnochs that are created when certain humans survive being attacked by an Orphnoch and become ones themselves, though weaker than the Original Orphnochs. But the most unique of type that appear in the series finale are the Evolved Orphnochs, the first of this type is the Orphnoch King, which are genetically perfect to the point of being unable to resume human form. An Orphnoch King can remove the genetic flaw from other Orphnochs, evolving them as well at the cost of their humanity.
All Orphnochs have their senses enhanced to a superhuman level, able to hear, smell or see great distances, tuning out background noise to focus on their target. They can also regenerate an ability as well as a first sense when the Orphnoch survived its human death, with the regenerating abilities depending on the Orphnoch in question. The stronger Orphnochs may fire energy blasts from their hands, though used a surprise attack due to its attack speed being slow and inaccurate for long distance attacks. But the Orphnochs' greatest ability is to 'siring' other Orphnochs (similar to Vampires or Werewolves) by attacking humans and (usually) stabbing them through the heart. This has a very low success rate, and usually results in disintegrating the human in question. Some Orphnochs seem to be capable of using long, skin piercing tentacles specifically for siring others. However, most cases of siring occur when the "sirer" is in Orphnoch form.
Every Orphnoch can interchange between their original human form and a unique Orphnoch form, light grey in colour with characteristics of either a plant or an animal with a body armour resistant to standard small firearms blasts and its strength varies wildly among Orphnochs as good measure of one's power. Only more powerful conventional weaponry can penetrate the body armour and harm or even kill some Orphnochs, while others can withstand even the basic attacks of the Rider Gears. Orphnochs can also generate signature weapons from their bodies. While in Orphnoch form, some of their kind can assume a Hybrid Form, becoming more creature-like in form. Few Orphnochs can assume a Secondary Form, increasing their standard Orphnoch form abilities at the cost of losing self-control. An Orphnoch can change their shadow into a hologram of their human form.
It is shown that Orphnochs heal their wounds recover quickly; Orphnochs can be seen injured when (a) small blue flame(s) burst(s) from their wound.