Terrorism in Dominions 3

[Sombre]

Well in that case you have to remember that the remote spells which actually do something resulting in a message will 99% of the time have the targeted player trying to work out who did it to them. They can usually work out who by considering the paths of the spell, who their immediate neighbours are etc.

Unrest caused by spies is something that they'd actively have to look out for since they won't get messages about it.