I saw the thread about Sins of a Solar Empire, and agreed with most of the criticisms people had about the game. Allow me to offer an alternative.

Designed for co-op play, Fleet Command pits a group of players against a pair of super powerful AIs attempting to wipe you, the last vestiges of humanity, from the face of the galaxy. To win, you build a fleet, find the AI home world, and destroy each AI's core computer.

At its heart, Fleet Command is an RTS, but with so many competing and conflicting design decisions that it just barely makes the cut. There are elements of 4X, tower defense and grand strategy, while really being none of these things.

There is no head-to-head option in Fleet Command. Instead Chris Park, its lead designer and programmer, decided to design what he calls an "asymmetrical RTS", that is, the AI you are fighting is many times more powerful than you and can crush you like a bug at any time, if you piss it off sufficiently. To support the asymmetrical design of the game, Park forgoes the usual "branching tree" decision-making AI that most RTS games use, bypassing the easily exploitable loopholes found in every other RTS known to man (see SC2 AI's complete failure against cheese). Instead, he coded a type of emergent AI that reads a huge number of variables before acting in any given situation. Park claims this makes the AI literally "uncheatable", and so far, I haven't seen anything to dissuade me of that notion. Indeed, Park claims the game has been doing things it wasn't specifically programmed to do since alpha.

A wonderful six-part essay on the logistics of Fleet Command's emergent AI can be found here if you're interested in learning more.

Basically, the AI in Fleet Command plays more like a human than AI has a right to, but the asymmetry of the game design makes it even more frightening. Be warned (or delighted): even though the game is rather slow (I prefer the term "stately"), it is deeply difficult. I've started many campaigns (which can take 20 hours or more on a standard 80-planet map), and only completed one of them on normal difficulty (AI level 7).

To sum all of this up: this game is brutal. You're going to get crushed. Repeatedly, probably. It's also beautiful, as the super old-skool graphics and gorgeous music coalesce into something that's as much an experience as a game. Most overlooked and underrated game of 2009, hands down.

If any of you pick it up, I'm SolidGod on steam.