- Patches of red scales along the Tiefling’s arms.
- Tiefling’s eye color is inverted in their reflections.
- Sheds skin once every 66 days, in the 6 days up to the molting the skin becomes gray and flakey, until it can be peeled off.
- Horns grow forever, and must be filed weekly before becoming heavy and hindering.
- Organs are reversed, pulse on right side etc. (I know that IRL the heart is in the center and only leaning left, suspend the disbelief please).
- No nose, rather holes that expand and shrink like a snakes.
- Smell with their (possibly forked) tongue.
- Can’t grow facial hair other than an ominous-looking goatee.
- Can’t lie while at least 25% submerged in a natural body of water.
- Sweat turns to steam immediately, although not boiling or even hot.
- Voice is a natural harmony, due to three sets of vocal chords.
- One hand has fingers with five sections each, the other has fingers with two sections each.
- Their horns grow like the branches of a tree and split at the ends that need to be trimmed like a bonsai.
- An insatiable lust for spicy foods.
- Sleep with eyes open and rolled back, snoring in ancient incantations.
- When sneezing, you briefly change appearance as if to polymorph into a demon or aberration of some sort.
- Your tail acts in the same manner a cat’s would.
- When inebriated instead of tripping over yourself or slurring your words, you gaze into nothing and whisper infernal phrases.
- Tiefling’s facial hair is constantly smoldering.
- Tiefling’s shadow is 3 times bigger than it should be.
- Tiefling has multiple pupils and/or no irises.
- Tiefling sees images of the Hells when looking through opaque transclusent materials.
- Tiefling has a strong inclination towards formal speech, documentation, and formatting agreements/relationships as contracts.
- Tiefling causes recently picked small vegetation to wilt immediately upon skin contact.
- Tiefling is nearly/completely identical to parent of the same sex.
- Tiefling derives a sense of comfort when faced with noticeable tension between two present parties.
- Tiefling cannot blink or shed tears.
- Tiefling has innate dislike of precise and/or complex geometric symbols.
- The Tiefling has two large horns, each of which has a red crystal carved/implanted into them.
- The tiefling’s tongue is that of a serpent, giving their voice a hissing sound.
- The tiefling’s eyes burn with the fires of their demonic ancestry.
- The tiefling is devilishly handsome.
- An Abyssal Rune is scarred into their back.
- Tiefling can smell any holy water within 20 feet, it is mildly irritating to them.
- Tiefling’s hands are backwards, their palms are where the backs of their hands should be.
- Tiefling has spines like a porcupine’s instead of head hair and facial hair.
- Teeth are regenerative.
- Sleeps hanging by tail like an opossum.
- Only has 8 fingers (including thumbs).
- Has two sets of eyelids.
- Can control body temperature (dropping or increasing at will by several degrees).
- Has a spellscar where sorcerers/wizards/warlocks can draw magical power from.
- Is disgusted by anything not humanoid.
- Breath smells like brimstone.
- Covered with birthmarks shaped like infernal symbols.
- Face always obscured in shadow.
- Flames flicker across the back of the hands.
- Each day a new tally mark scar appears on the skin.
- Tiefling is blue and cold to the touch.
- The tiefling’s preferred sleeping spot is a burning coffin.
- Tiefling has tusks instead of fangs, almost like an orc’s.
- Makes domesticated animals nervous–disturbs messenger pigeons in their roosts, sends cats yowling from the room, etc.
- Has two little nubs on the shoulder blades where wings would ordinarily be.
- Infernal Shadow: this Tiefling’s shadow has its own weight, even though slight, is noticable by other creatures when it rests upon them.
- Antlers that grow like a wreath starting 2″ behind the ears moving forward.
- The tiefling has pearly black skin with gold marble veins.
- Vertebrae are raised slightly, like pointed peaks.
- Secondary set of eyes set below a typical pair, one set for normal light, the second for darkvision.
- Only sleeps standing up.
- Leaves behind brimstone soot on surfaces, especially in it’s bed.
- Spilled fresh blood is dark and gets brighter as it ages out of the body.
- Hair flows and floats as if underwater.
- Reflections are tripled.
- Bones feel creaky under a full moon.
- Four extra canine teeth on the top and bottom jaws.
- Each step made on earth bare-footed leaves a charred footprint.
- Hundreds of healed gashes cover your back, Though you’ve never been whipped.
- You carve tiny apocryphal sigils into your skin with fingernails as you sleep. If someone with a mind for puzzles and a knowledge of infernal can decode the script, it will reveal a minor demon’s true name.
- Your tail, if somehow detached from your body, will grow back in a month and a half, as the old one turns to a jagged obsidian, too brittle to work.
- The Tiefling’s shadow shivers visibly, and sometimes twitches and jerks in an unnatural manner.
- The Tiefling attracts their own blood gravitationally, with the blood being otherwise unaffected by gravity.
- The Tiefling’s tongue is covered in sharp teeth.
- Small clouds of soot appear as the Tiefling exhales.
- The Tiefling’s teeth can be folded backwards like those of an anglerfish.
- The echo of your voice returns in Infernal.
- Followed by a loyal servant that no one else can see, hear or feel.
- When laughing nearby fires sputter, spark and release sulphuric smoke.
- In the presence of priests, monks or clerics can only speak in sing-song rhymes.
- The slightest touch on their skin leaves a black imprint that fades a few seconds after the pressure stops.
- Their blood glows like magma, and turns into solid glass/obsidian soon after leaving the body.
- Pupils/irises look like a highly reflective metal and act as mirrors.
- A ring of long, soft fur grows around the tiefling’s neck.
- Long, black claws in place of nails that cannot be cut, only filed.
- Candles are snuffed as if by wind in their presence.
- Short, bobbed tail where a long, pointed one ought to be.
- All bodily fluids (blood, spit, etc) are pitch black and shine like oil.
- Grass dies wherever they stand, sit or lay for an extended period of time.
- With every beat of the tiefling’s heart there is a surge of heat through it’s body.
- You are inexplicably drawn to music, but you can never understand how to create it.
- Small, heatless flames flicker across your skin when you’re angry.
- You understand the thoughts of reptiles.
- Any fire within 5 feet of the tiefling burns dimmer, but hotter.
- All bodily fluids are replaced with blood. You will cry, urinate, vomit, and sweat blood.
- Their breath is icy cold and fogs in all temperatures but the coldest of winter.
- Their only otherworldly feature is their horns, which they constantly file close to their scalp to attempt to look more human.
- Has an extra set of teeth on their lips, outside of their mouth.
- The tiefling doesn’t open its mouth to speak. It’s voice seems to emanate from some source deep within the bowels of the creature.
- Shadow effects physical objects by touching their shadows and is darker than normal.
- Naturally black bones.
- Hair grows in different colours randomly.