Arcane dragons bleed with a slight pinkish shade, and the blood has a pearlescent and sparkly look, like taffy being made. When a scab forms over a wound it turns a dark deep purple but retains the sparkly texture and ends up looking like the night sky, but spilled blood evaporates into purple mist instead of clotting.
Earth dragons bleed pretty normal color-wise, but the blood feels grainy and sandy to the touch, and the scab it forms is tough as rock and can sometimes form into a gem-like shape. Spilled blood clots into little dark-red pebbles, which some dragons treat as pearls, though most prefer to just let the blood stones be. There is a somewhat taboo tradition of using the blood pebbles of a loved one who passed away to make a necklace or bracelet.
Fire bleeds an orange glowy blood that is very hot to the touch and resembles magma. It scabs into a rough and kinda flakey black-brown patch, but spilled blood can catch fire very easily and will leave behind scorch marks if it lands on fabric or fur.
Ice, like Earth, bleeds pretty normal at first glance, but the blood feels of course very cold to the touch, and licking/drinking it will make your breath go misty for a short while. It scabs into a smooth translucent red sheet, and clots on surfaces as a thin layer of red ice.
Light bleeds bright white blood, period. It glows white, it is white, it scabs into faintly-glowing white stuff, it never stops glowing even when clotted into beads on the floor. Some Light dragons collect their own blood in glass jars and use it to keep their homes lit.
Lightning… hmm. I guess Lightning dragons would bleed a sort of ferrofluid equivalent, which I guess is more magnetic than electric but that’s the only thing I can think of.
Nature bleeds a very thick, translucent blood, like tree sap, which scabs into something that looks like bark and clots into an amber-like solid that can actually trap insects and other small critters inside it.
Plague bleeds regular blood, but it has an unusual tendency to bubble slowly and send off droplets abnormally far. The scabs are thin and crack very easily, and when spilled the blood can sometimes turn into a sickly shade of green and become extremely sticky and virulent.
Shadow bleeds thick inky black, and a single drop of Shadow blood can tint a whole barrel of water as black as night. The scab absorbs light and is relatively smooth, and the black bloodstains from spilled blood are nearly impossible to remove, be it from the ground or from clothes or fur. If allowed to clot/dry the spilled blood will stick to whatever surface it landed on and stain it black forever. Some Shadow dragons use their own blood to write instead of regular ink.
Water blood looks diluted and anemic, with a pale translucent red and a very fluid, watery texture. It barely scabs and when spilled spreads and flows like water, hardly staining what it touches, and rather than clotting it just turns into a stringy gel, like hagfish slime.
Wind dragons don’t bleed so much as leak a dark red mist from their wounds, though the mist condenses into regular blood upon touching any nearby surface. The scab it forms is flat and smooth, and if left alone the condensed blood will slowly evaporate again, leaving behind only a faint red bloodstain.