If any player rolls a "7" on his turn, the robber is activated. First, his pawn is moved to any hex on the board and production is shut down on that hex. Also, the player who activated the robber can steal a random resource card from any player with a settlement built on that hex!

Players who hoard too many resource cards will find the robber affects them too. Anyone with over seven cards has to discard half of what they hold.