Command and Conquer Red Alert is a classic 1995 real time strategy that has been released for free download. In this game, you control harvest resources in order to buy buildings and units to that you may command and attack with. the 2 factions are the allies and the soviets who offer different gameplay styles. The controls are limited to one button. This makes it simple to learn but commanding troop is clunky at times. This game contains the full single player campaign of both the the allies and the soviets. Online play is possible but requires 3rd party software to work.
This game is 100% free