What are some general clues that indicate if someone is playing the role of saboteur? Obviously if player is going to put a troublesome dead end on the only path he's a saboteur. But some players are more subtle, and they come out of cover late in the game. How can I spot a saboteur early on in the game?
And if you still don't know, just call them a "saboteur" and see what the general reaction is. :-)