The players must try to build the most valuable, or the most useful districts. However, the core of the gameplay revolves around role selection. Players secretly choose a character card and pass on the rest – starting with whoever has the crown. Each character has a special ability, and the usefulness of any character depends upon your situation, and that of your opponents. If you are too obvious in your movements, you may meet an untimely death at the hands of an assassin, or a thief may whisk away all of your precious gold.
Once someone has built eight districts, the round continues until all other players have taken their actions, and then the game ends. The player with the most victory points wins. Victory points are determined by the gold value of buildings, but it is also important that players have a varied city, and complete their districts with haste if they are to see any bonus points.
Citadels had a separate expansion, Citadels: The Dark City Expansion, but the new (3rd Edition) Fantasy Flight edition comes with the expansion included (the Hans im Glück tin box also included it). With the newer version that includes Dark City, or the Dark City expansion purchased separately, Citadels supports a maximum of 8 players.
A second edition of the German version of the game came in a tin box and included the Dark City expansion as well as three additional cards. It is separately listed at Citadels.