Bill Cipher’s powers are interesting
So far Bill hasn’t directly killed anyone. What he (and his eye bats) did do was petrify a lot of people.
Something about this reminded me about Bill’s abilities in the first episode involving him, Dreamscaperers.
Nightmares, dreams that induce fear.
Bill is literally powered by fear.
The British dog-man that torments Soos seems to be from a recurring bad dream. Mabel apparently has nightmares where she is no longer cute.
These are all conjured by their fears, but how did Craz and Xyler show up? Simple they are something that reassures Mabel and alleviate her fear which is the other side of Bill’s powers.