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Freeciv is an open-source, turn-based strategy game based on Civilization II. Inspired by the history of human civilization, the game commences in prehistory and your mission is to lead your tribe from the stone age to the space age...

Hedgewars is a turn based strategy, artillery, action and comedy game, featuring the antics of pink hedgehogs with attitude as they battle from the depths of hell to the depths of space. As commander, it's your job to assemble your crack team of hedgehog soldiers and bring the war to your enemy.

FreeCol is a 4X video game, a clone of Sid Meier's Colonization. While remaining faithful to the original in terms of mechanics and gameplay, FreeCol sports a new set of redesigned graphics. Moreover, in addition to the classical Colonization rules, it features an additional ruleset that incorporates ideas that didn't make it to the final version of Meier's game, requests by fans and original concepts like new European players with new national bonuses.

TripleA is a free (under GPL) turn based strategy game based on Axis & Allies board game. A wide variety of map scenarios have been developed for TripleA (World War II, Punic Wars, Napoleonic wars, etc.) with a variety of rules, units and many options (such as "low luck" which reduces the number of dice rolled making game depend more on strategy).

Duel of Tanks is a turn-based strategic artillery game primarily focusing on multiplayer PVP elements. Demolish players from all around the globe with a huge collection of upgradable weapons in one of the unique battle arenas. Each arena has different rules and increasing difficulty level. Earn experience, level up and unlock new weapons to dominate your opponents. Alternatively you can play against skilled AI bots in head-to-head matches.

Pocket Tanks is the fast-paced artillery game that is simple to learn, and fun to master. Bury your opponent in a mound of dirt, or assail him with a barrage of bullets. Visit the Weapon Shop before battle to arm yourself for the struggle, or try the Target Practice mode to learn all the weapons and the best tactics to win. There are many unique weapons including: Napalm, Firecrackers, Skippers, Cruisers, Tracers, Dirt Movers, and dozens more!

webDiplomacy is a multiplayer, online version of Diplomacy, the popular turn based strategy game in which you battle to control Europe; to win you must be diplomatic and strategic.

Great Little War Game is a 3D turn based strategy game from Rubicon.

Annihilate the other tanks to earn money, then spend it on bigger and better shields and weapons to wipe out the opposition. Features a wide array of weapons, AI players, destructible landscape, weather, parachutes, teleports and a wide range of other features.

World Conqueror 1945 is a strategy game based on WWII (Super Risk). Compete for territories, conquer enemies' capitals, and destroy the enemies.

Port of Freeciv to Android - similar to Civilization series.

It is the year 2077, for the first time in its history mankind has finally began the colonization of another planet. Will the pioneers from Earth succeed in colonizing their new home or will they fail to survive against the harsh and inhospitable conditions of the Red planet?