I’m a bit confused on Gears, they technically aren’t 100% they’re own original species since to make them you need other organisms right? (Like humans, animals etc like Sol) So they’re kinda a hybrid of gear and whatever species was used to create them. So if Dizzy and Sin are considered human gear hybrids, wouldn’t that make other gears like Sol and Justice human gear hybrids and not pure gears?
This goes back to what I said earlier about Asuka’s methods when he first created the “Gear Archetype”. Asuka was looking for the perfect biological vessel.
What determines what is and is “not” a “pure Gear” has more to do with the Prime Field, the original Gear Cells that Asuka, Frederick, and Aria created back when the Gear Project was first established.
I wouldn’t necessarily describe it as a “royal bloodline”, but in a sense it is, as it involves the Prototype (Sol), the Progenitor (Justice), and subsequent Inheritor generations (Dizzy, Sin) and Derivatives (Valentines, Ky, Solaria, “Neo” Aria).
What “defines” a Gear, is more or less whether or not they possess Gear Cells (or more accurately, a ‘body’ or ‘body parts’ made of Gear Cells). The Bloodhound Dog and Owls that attacked Frederick in the research facility (in GG Begin) are a prime example of “basic Gear subject/samples.”
What “defines” a Humanoid Gear (or even a “Sentient” Human-like Gear), has more to do with the Intermediary (Testament, Dr. Paradigm, Gig, etc). Gears that have existed for a long time and “evolved” Sentience (self-awareness and thought, also identity) also fall in this category, though by this point they are closer to a Youkai if one were to compare. Gears that originally had humans as their base Intermediary are more likely to retain their sentience (Testament), but some do not (Sheevus).
The “Intermediary” is the former soul/lifeform that was used as the base for the Gear, and copied (dubbed) over. This could be any animal, any human, or possibly even both or multiple (Leopaldon is one such rare case). However, the “dubbing” process is imperfect, and even the Gear Cells have certain flaws in them, so they are not without vulnerabilities/failures. Even the copying process could be considered “death” for the original subject.
Dizzy is a “manufactured hybrid” (a Backup of Justice, similar to Valentines) while Sin is a “genetic hybrid”, and in Ky’s case, he most likely underwent a medical procedure to gain his Gear Cells (which is more often than not very risky).
“Frederick Bulsara” and “Aria Hale” were the Intermediaries of “Sol Badguy” and “Justice” respectively, so they are complete Gear-Cell body conversions (much the same as Testament later was), as their entire bodies were remade/grown from Gear Cells (most likely killing the original subject in the process, even if the soul was ‘dubbed’ over and memories semi-retained).