1 to 5 Players Citizens of the Spark is a variable setup card game where players compete to build the most successful city by recruiting anthropomorphic animal citizens with unique powers. Players take turns attracting groups of citizens from a central market ("the Assembly"), adding them to their personal city tableau. The more cards a player has of a specific citizen type, the more powerful that citizen's action becomes when activated.

The Transmission Pack mini-expansion adds 3 new types of citizens: the Advocate, the Pillager, and the Warden (30 cards total), as well as corresponding randomizer and solo-play cards. This expansion provides even more variety and millions of possible combinations for fresh strategies in every game.