growing meat stick on your meat keep all the pointy objects out.
Either reanimate with necromancy and lax corpse disposal protocol or growned in vats or degenerate peoples that are so degenerate you can wear them as a helmet
You can eat it
Relatively easy to adapt to your system
I Think I hate this format I'm just going to skip to the fun bits
Who can hook a girl up?
Necromancers or golem crafters that deal a specially with flesh. Cults. Always the cults. These ones worship a perfect cube of meat. Womb witches take carefully regulated doses of terragens in order to give birth to graftable components.
A people that are always born with a conjoined twin that they separate themselves from in a coming of age knife dual and then keep the bits of the twin around for trade/spare parts.
Dr Moreau types.
It's a little version of you inside you that suffers instead of you.
Any spells or maledictions effect just the homunculus not you. Which might kill it as it has no special powers of regeneration or resistance. Despite its "saint" title , it fucking hates you , but lacks the strength to claw its way out, but if someone knows it is there , they can target it with beneficial magics , maybe empowering it to eat your heart. So .. watch out for that.
Cysts storing poisons, potions or acids , to be released from blunt trauma
like a fat suit but more of a hollowed out ogre you can climb inside and wear as an exoskeleton, but kinda the exact opposite of exoskeleton but not really I guess??
Your milk production glands are replaced with something that duplicates a spell like charm person or web or melfs acid arrow. But via milk.
Let's presume there were no metaphors in Shakespeare just literals.
Is this even armour anymore, it's just turning into a list of body horror you can shop for. Anyway every time you come to a major decision point in your life, the type that forever shapes you in a different direction,
you grow a smaller you just under your skin. If you die, your outer layer peels away and a you that would of made the other decision steps out all naked and glistening and with actual memorys up until that point, and then hazy not real memorarys beyond that , as if they had been living out that alter life path you did not take.