Impostor

Impostors are a sapient species that has infiltrated multiple facilities of the Crewmate space program with the intention to kill everyone working in them. An Imposter perfectly mimics a Crewmate space suit, except when its mouths opens to use its tongue as an impaling weapon. Impostors have superior low light vision to crewmates. They also have technology to remotely sabotage insecure Crewmate devices.