From Divinity Engine Wiki
- event CharacterReservedUserIDChanged((CHARACTERGUID)_Character, (INTEGER)_UserID)
Thrown when a character gets assigned to a user, or when a character no longer is assigned to any user.
- _Character: The character that was (re-)assigned.
- _UserID: The id of the user to which which the character was assigned.
- When a character is no longer assigned to any user, i.e. if it was a player character and was then made an NPC, _UserID will be the reserved value -65536.
- A character can either be explicitly assigned to a user from story, or by the game engine when a new user connects to a game. In both cases, this event gets thrown.