Replay Value: 8/10
Scoundrels of Skullport is an expansion to Lords of Waterdeep (which I reviewed back in November). Released in 2013 it includes two different expansions, three new boards and a mountain of new Intrigue and Quest Cards, as well as new buildings and Lords.
You can use one or both of the new expansions. Using only one expansion means adding 3 buildings to the base board, but has no other effect on set-up. Using both expansions adds 6 buildings to the board, and each player gets another agent.