#this has been simmering in the brain soup for a while but smtl provoked me

[blorb-el]

actually though. various (sfw) kryptonian biology headcanons that skirt right up to human-passing

- higher base body temperature

- pupils that aren’t black but instead shaded slightly in the color of the iris. all kryptonians have unnaturally vivid eyes but it’s hard to tell exactly why unless you’re literally gazing into them

- tapetum lucidum (reflective eyes like animals) a bit harder to get away with, but are extremely funny because clark often does the maneuver where he’ll stand in front of a car to stop it, and this would make seeing him like seeing a deer but 10000000% worse

- they are actually bioluminescent it’s just that under normal circumstances it’s in the ultraviolet and we can’t see it. clark goes off to a blue sun mission and comes back looking halfway to electric blue superman. glowing stripes and freckles

- non-newtonian dynamic to their skin/flesh where it gets harder with more force applied; nothing unusual to the feeling of a normal handshake, but a punch thrown with force will break bone

- retractable fangs au because bonus teef are fun

- i swear some comic somewhere said something about nose gills

- solar lymphatic system primarily distributed along the spine. the entire spine lighting up with heat vision...

- they can collapse/skrunkle their spine a few inches; helpful with secret identity, but it restricts range of motion so it has the side benefit of making them a little clumsier

- blood tinged gold with stored solar energy

- just enough extra twist in their neck to enter uncanny valley territory - not quite looking straight behind but enough to be creepy as hell. kara would do this all the time

- golden age face squooshing. i do not think this should come back but it was actual canon for a while that they could just contort their faces. again creepy as fuck