Strategies

UFO: Alien Invasion is a free and open source, multi-platform, real-time strategy and tactical role-playing game

Slingshot is a free and open source 2D turn-based strategy simulation game set in the gravitational fields of several planets

KsirK – free and open source computerized version of the well known strategic board game Risk

Konquest is a free and open source galactic strategy game, version of Gnu-Lactic Konquest, players conquer other planets by sending ships to them

Hedgewars is a free and open source, multi-platform, fun turn-based artillery strategy game with war hedgehogs