7 Wonders: Cities, the second expansion for 7 Wonders, includes optional team rules, adds an 8th player (base game supports 7 players), a new type of card (black, representing the remains of cities), and new cards of old types (two new wonders: Petras and Byzantium, 3 new guild and 6 new leader cards). This expansion is more aggressive, with greatly increased interaction between players, who are still trying to score more points than anyone else.