Kasaavin
The Kasaavin were beings that could phase through walls, even those of the Doctor's TARDIS. They took humanoid and shining bright white light form while allied with the Spy Master, but explained to the Thirteenth Doctor that this was because the human shape "amuse[d them]." When they emerged through a surface, they temporarily took the image of that which they had passed through.
The Kasaavin planned to "take" the Doctor's universe. (TV: Spyfall) The Kasaavin, along with Daniel Barton, were unknowingly part of The Master's plan to destroy humanity and rain destruction across the universe before The Master's plan was ultimately foiled by the Thirteenth Doctor and her companions. The Kasaavin are capable of transporting beings on Earth to the Kasaavin's native dimension and transporting them back. The Kasaavin appears to be able to travel through time as they appeared in several time periods on Earth. In Spyfall part 2, it is seen that devices know as "silver lady" were used to deliver the Kasaavin to Earth, so it is likely that the Kasaavin cannot travel on their own, and need a portal of some sort.
Behind the scenes
- The Kasaavin were voiced by Struan Rodger
