Long ago, the galaxy had known peace. Paradise was ruled with the hand of science, and the hand was that of the galactic governing body known as the Core. Ironically, it was the Core's ultimate victory, the victory over death itself, that brought about the downfall of its paradise and started the war that would decimate a million worlds. The immortality process, known as "patterning," involved the electronic duplication of brain matrices, allowing the transfer of consciousness into durable machines. Effectively it meant immortality, and the Core decreed the process mandatory for all citizens in order to ensure their safety. However, there were many citizens unwilling to toss aside their bodies so casually, many indeed who regarded patterning as an atrocity. They fled to the outer edges of the galaxy, forming a resistance movement that became known as the Arm. War began, though it was never officially declared by either side.
This is only for those who can appreciate old games and look past the dated visuals. If you can't, go play something else because this game won't be for you.
Plenty of unit variety, a thriving modding community, an excellent soundtrack and many more things make Total Annihilation a truly fantastic RTS of it's time. This game, in my personal opinion, is better than a lot of modern RTS games.
You can purchase this game, complete with The Core Contingency and Battle Tactics expansion packs, via digital download on Impulse for £7.99 GBP or $12.87 USD. It works fine on Win7/Vista :)