Smallpox is the unofficial term used to describe the most prevalent strategy used in Freeciv today. To seasoned CivII players, it is known as ICS — Infinite City Sprawl/Sleaze. It refers to the practice of building lots of small cities, normally no bigger than size 2 or 3, often close together, with only one space in between. It is wildly popular because it enjoys several distinct advantages over other civ building strategies, especially at the early stages of the game. These advantages include, but are not limited to: