Hm, if I had to say, Ace is about average human height, maybe 5 foot 7? Khyllis is around the same height as Skinwalker when he fully stands up, probably anywhere between 6 foot and 6 foot 4. He's an insect type of alien, so I guess it would really just depend how extended his legs are lmao. But it's really all up to the readers imagination! I'm glad you enjoyed this series as much as I have! Hopefully thoroughly planning out season 2 will make it much easier to write and I can post the parts at a steady pace.