0 A.D. brings familiar straightforward real time strategy gameplay for free using open source code. With a mini-map in the bottom corner, resources shown in a bar at the bottom and of course unit selection through double clicking, all of the major elements found in most RTS games is here, making for a very familiar game for those that are used to the genre.
By being in active development the game allows for frequent bug fixes as well as frequent new content. While it is still in alpha, the state of the game playability is pretty good with new features being added all the time.
When it comes to a completely free RTS that is being actively developed there are few options, or really only one, this game. So for that part, the best option available as it is really the only one. While there may be some free to play RTS options available they do rely on in game transactions where this title will have none.
The game will run on Linux, OSX and Windows, which is great for people who dual boot or just use multiple OS's across their devices. No matter the OS used, one can install and play this game.