Has anyone tried and can tell me if it’s a solo game or not? GMless or not?
CAIN probably runs best as a group game due to how (relatively) lethal a session or Hunt can be. A GM is required in this case to set up the investigation for the players.
I think Solo Play is possible, I've certainly tried (and am trying) workshopping a system to do so, but it will require making some adjustments to how investigations are run.