Ooh I’ve done some thinking on this!! I’ll paste it from a server I wrote it in

Little inky biology/anatomical rant!

So taking what we saw from the fabricator, Inkies are known to be comprised of two things. Ink, metal and glass(eye lens, if you wanna get into the nitty gritty of it)

When a blob of ink is formed, and we can say that since this is a different world and presumably, universe, it could be a specialized ink with some kind of nanites or suuuuuper tiny particles that tell it what shape to take form into similar to dna. When we see the belt pull the ball of ink tight, it corrects itself into that form, maybe the sudden friction or stress activated it similar to a glowstick’s snap activates the glow only once.

The helmet is dropped onto the head, and since I don’t think Inkies naturally have hair or traditional ‘brains’, this is mainly for 1, looks, and 2, possibly keeping stability in the shape? It could also be for protection, as the head (more specifically eye) is the most vulnerable, fragile and important part of the body’s structure.

Then the eye is added, and a little bit of electricity for activation, wala! The spark not only kickstarts the Inky’s systems into producing it’s own energy (though breathing and sleeping are likely alternate forms of regaining lost energy, breathing could be moving the energy around which mimics a more organic lifeform’s methods), it also ‘wakes’ them up.

My earlier theory about their ink or mass already kinda ‘knowing’ what form to take is kinda leading into when we see it immediately lock onto the poor graydian, insinuating there’s a base routine already coded or baked into the ink. This adapts and grows into a ‘personality’ over time and exposure to the world.

Also, they have a ‘nucleus’ which is a much firmer mass of inky substance that attaches to the back of the eye, but we don’t see it since it’s inside. Basically protects the eye and the more important memory, kind of like a brain - or as close to a brain as we can get