Saboteur 2 is NOT as stand-alone expansion and requires Saboteur to play.
You are dwarves digging for gold in the depths of a mine when suddenly, the pick-axe breaks, and the lantern goes out. The saboteur has struck again. But who is the saboteur and will he (or they) stop you from reaching the treasure? If you succeed, gold awaits you. If you don't, then to the victor goes the spoils. Whoever has the most gold nuggets after three rounds is the winner. A path-laying card game where each player has a role and no one knows for sure what that role is.