Always Chaotic Evil denotes an entire species in a fictional setting as outright evil - no matter how one treats them, they reward kindness with treachery and violence. Frequent recipients of this trope include but are not limited to aliens, demons, vampires, zombies, trolls, dragons, ogres, goblins, werewolves, giants, orcs, dinosaurs, and scorpions. I mention this because my trilogy has a species called the Degenerates, who are an antagonistic force for the trilogy's first half.
The Degenerates are genderless humans and animals who share similarities with a parasitic extraterrestrial thanks to being parasitised by prehistoric pentastomids and style themselves after various nomadic Indo-Iranian cultures. I've tried avoiding portraying them as violent savages by justifying the Degenerate's aggressive tendencies via implying Degenerated animals are slaves to the pentastomids' desires. While some Degenerated humans retain enough humanity to even be sympathetic characters, with their "king", Koloksai being a polite, idealistic and moralistic individual who wants to eradicate every form of discrimination by turning humans in Degenerates while founding a proto-nation where they can live centuries-long lives in harmony with nature.
But when all is said and done, I feel that this still isn't enough to avoid characterising all Degenerates as bloodthirsty barbarians.
How can I avoid falling into such a trap?