Vulpkanin do not have any cold resistance or heat weakness. Their ability to withstand high or low temperatures is the same as humans. The only non-cosmetic things they have are nightvision when wearing mesons (Same as Tajara), sharp unarmed attacks, slightly less alcohol resistance (Their alcohol resistance is 1.4. Humans have 1.0, and skrell have 4.0, for comparison) (Same as Tajaran), and the ability to eat mice, lizards, chicks, chickens, crabs, butterflies, parrots, and tribbles (Same as Unathi). The nightvision while wearing mesons thing is really the only part that affects gameplay, the rest is mostly fluff. Unarmed attacks generally aren't used when you're trying to kill someone, at least in my case.