"MegaGlest is an entertaining free (freeware and free software) and open source cross-platform 3D real-time strategy (RTS) game, where you control the armies of one of seven different factions: Tech, Magic, Egypt, Indians, Norsemen, Persian or Romans. The game is setup in one of 17 naturally looking settings, which -like the unit models- are crafted with great appreciation for detail. Additional game data can be downloaded from within the game at no cost.
MegaGlest is heavily based on the widely known Glest, which it forked from in early 2010. In early 2012, MegaGlest has started replacing Glest in major Linux distributions. Like its predecessor, MegaGlest is available under liberal licensing terms and can be downloaded and played free of charge."
Source: The Game Website.