But I see. [Looking more thoughtful now.] In theory, the equivalent to these "aer krenes" may be the locations where the spirits were found in my world. I've noticed there were higher concentration of mana from each though the world tree has always been its main source. Perhaps that last stable aer krene is the same, hence why you were able to convert the Apatheia. Please tell me, how many have you converted to spirits including their names?