Chris Beatrice Interview
ARR: How will "building colonies" be implemented?
Chris Beatrice: That's another one that's tough to answer simply, without first establishing some basic understanding of how Zeus scenarios differ from those in Caesar III and Pharaoh (this pertains to question 7 below as well). In Caesar III and Pharaoh, as you know, a "mission" involved developing a single city from the ground up to completion, and achieving certain goals with that city in order to win. A "campaign" (there was really only one campaign in each game) was a series of these missions (i.e. cities) strung together to form a larger whole. In Zeus, a campaign (we're calling them "adventures", at least for now) involves the creation of a single parent city, and one or more colonies - known collectively as a city-state or "polis". A "mission" is really just one of the goals (which can be relatively minor) you'll have to achieve as you develop this little empire. Mission goals can be things like achieving quests, slaying mythical beasts, making allies, establishing colonies, and so forth. When you achieve a mission goal, you go on to the next mission, but that doesn't mean going on to another city. It may mean picking a location and setting up a colony, or it may mean returning to the parent-city from a colony, or it may mean staying in the parent-city and developing it further.
So, to answer your question, a colony is one of several cities that comprise the player's city-state or "polis". Each campaign normally provides a number of viable locations on which the player can establish colonies. As the player moves through a campaign, achieving certain goals, s/he'll be given the opportunity to temporarily leave the parent-city in order to establish a colony. S/he can choose from any of the viable locations, at which point play moves to the city level at that location. The player then builds the colony as a standard (though smaller and less robust) city, while interacting with his own parent-city on the world level (asking for supplies, sending resources, and so forth). When the colony is up and running, play returns to the parent-city, and now the player can interact with the colony s/he's established. When it's time to establish another colony, the player chooses from the remaining viable locations, and so on.
Colonies are crucial for a number of reasons, the most obvious of which is to provide a steady supply of resources, allowing the player's polis to be largely self-sufficient (or at least allowing the player to blow off an ally if s/he wants to!).