The A.I. is the most intelligent opposition I have ever seen in a strategy title, and the tech tree is vast enough to offer a plethora of various strategies to employ. The lack of multiplayer is ameliorated by the fact that there are so many options and ways to play the single-player portions.
Dark Avatar does what a good expansion pack should -- it makes it tough to imagine ever playing the base game without it. It makes a great game greater, even if its achievements are measured in pinky widths instead of leaps and bounds.
Above all, compared to almost any 4X game out there, it's the AI that stands out in Galactic Civilizations. It doesn't cheat, except at the highest difficulty levels, and it behaves in believable ways. It exploits weaknesses, it doesn't gang up on the player, and it uses sound strategies.
SummaryThe year is 2226 and the Drengin Empire reigns supreme across the galaxy. But something utterly evil is devouring the Drengin Empire from within. Expand your Galactic Civilizations II experience with espionage agents, player designed opponents, new alien races, new ships, unique planetary environments, asteroid fields, improved graphics ...