From publisher blurb: Alien Evolution takes the concepts of Traits and creates a system for you to quickly add strange and unusual features to any race and create diverse species. Antennae on humans, blue-skinned elves, and tentacle dwarves are just a few ways this system can add diversity on the fly as your players travel a multitude of strange worlds. This system is also perfect for players to create new racial variations without having to create entirely new races or finding one that fits their ideas, and allows them to do it quickly! Players may choose up to two of these Evolution traits (or mix and match with standard traits)or choose a drawback to receive a third Evolution trait.All races are free to choose Evolution Traits.