"C-evo (a.k.a. Civilization-Evolution) is a free turn-based strategy computer game written in Delphi, with the majority of design and programming done by Steffen Gerlach. The source code is in the public domain, but the graphics are freeware. C-evo is based on Sid Meier's Civilization II, but with the aim of correcting design mistakes by implementing six design principles which correct the game itself and strengthen its weak artificial intelligence. Source: Wikipedia, "C-evo", available under the CC-BY-SA License.