Chryssalid

Chryssalids are swift, four-legged aliens with terrifying melee capabilities and a fairly strong poison. Strangely, their poison is ineffective against other aliens. When a Chryssalid kills civilians or  soldiers, it will implant an embryo in them. This causes them to rise again as zombies, which will spawn a hatchling soon after. The one difference between an adult Chryssalid and a hatchling is that, being technically newborns, the hatchlings don't have the carapace that full-grown Chryssalids have.

Chryssalids only weapon is their claws, which, coupled with their speed, makes them effective against most targets. However, flyers such as the Floater have proven to be the bane of this creature, able to fly out of reach and fire down on them.