-Viltrumites don't have superhearing(volume) but have superhearing(frequencies). Their native language, when spoken normally, is in a frequency higher than humans can hear, with it getting higher in frequency the more urgent or excited the viltrumite is. On the flipside, viltrumites use frequencies lower than what humans can hear for soothing others. The lowest frequencies are reserved for seduction and intimidation/aggression.
-Viltrumites have a similar sense of smell to humans but are especially sensitive to the smell of blood and sweat.
-Viltrumite teeth are built for ripping meat and crunching bones. 95% of their diet is raw alien flesh and bones+whatever alien fruit or vegetable they happen to find so their teeth structure is omnivorous, though they have four extra teeth that humans don't. These four extra teeth sit opposite to the canine on the opposite mandible, which sit out just enough for the extra teeth to close behind them, making escape all but impossible. Their teeth are deeply rooted, like a dog’s, so they're harder to pull out as well.
-Bodies are covered in stretch mark-eske stripes. The older they are, the more intricate and numerous the stripes. They get their first stripes when they gain their powers.
-Viltrumite nails naturally thicken and curve down into claws if left to grow.
-Hair, both body and facial, grows faster
-Viltrumites have a second growth spurt between 20-30 and continue growing, though extremely slowly, for the rest of their life, averaging between 6-15cm/2-6 inches every thousand years
-They purr when they're content and will hiss, growl, and snarl when pissed.
-They have a prey-drive and will chase if you run.
-They scentmark anything they view as theirs.
-Viltrumites have a nictitating membrane to protect their eyes in battle. They also have tapetum lucidum.
-When fighting, their saliva will thicken and sometimes even become foamy. Their blood will also mix in with their saliva, giving it a pinkish red hue and making them look rabid(they can't get rabies though).
-When preparing to impregnate and during the pregnancy of a mate, viltrumites will tend to overhunt and overfeed their mates so they have more energy/nutrients for an easier pregnancy.
-Will carry babies similarly to a cat or dog(viltrumite babies have stronger neck muscles than human babies).