a magic system where practitioners slowly adopt the form of whatever their mind is, because even when you form the world with your mind, you're still part of that world and your mental habits leak
few stay human, of them many switch sex, advanced practitioners are barely recognizable as sentient or even a coherent entity: one's a walking void, one's a stalking tangle brass rods and lenses and prisms, another is a swarm of locusts
and when two wizards love each other, their aspects intermingle, a giant spider grows scales of gold while the clockwork starts looking more organic and web-like