Psions are a unique rank that only the Ceasan's hold, it is an Ceasan who specialises in the use of psionic powers, while being weaker in other respects. Despite specilizing in psionic powers Psions are the weakest psionic user, with Ceasan Officers , Leaders and Preator's surpassing Psions.

Psions only appear onboard Scout UFOs and small Ceasan Alien Bases . They are replaced when Officers start appearing.