This expansion to «Startropolis» adds three optional features to gameplay: new advanced modules, alien factions, and secret missions.
There are six new module types, each with its own components, capabilities, and advanced modules card. Each of these are meant to be substituted for one of the basic module types in the core game to make for many possible variations.
Alien factions make for an asymmetric game, with each player having both a special permanent ability and single use ability. Secret missions add a hidden information element making it harder to estimate the progress of other players.