My friend palace recently uploaded a video regarding CoS and a general ARG announcement. pretty informative.
https://www.youtube.com/watch?v=Xurl7jh6d7I&feature=youtu.be
CoS = Church of Scientology
CoS = Cult of Saturn
CoS = Church of Satan
CoS = Chief of Staff
CoS =
cave of shadows. the only CoS ARG around to my knowledge