I know there are many fans of strategy here and Certis gave me his blessing, so I figured I'd go ahead and start a thread about my fresh new 4X game: At the Gates.
Anyone who listened to the February 6th GWJCC already knows the skinny, but if you haven't heard it, the basics are that this is an empire builder where you lead a barbarian kingdom during late antiquity as the Roman Empire is falling apart. ATG has many of the typical 4X tropes like exploration, diplomacy, resource management, etc. but it also spices up the formula in a couple big ways.
First, the map changes over time with the seasons, requiring you to plan ahead with both your military campaigns as well as your economy. The landscape gets cold and hostile, normally-impassable rivers freeze and become crossable, etc.
The other big bullet point is that the pace is different from most 4X games. Instead of starting off fun and interesting but losing steam in the midgame, ATG actually gets tougher the further in you get. Resource deposits deplete over time, forcing you to either grab new ones from your neighbors, or migrate your entire tribe to another part of the map.
There's a lot more cool stuff I'd love to share with you guys, but I'll try not to ramble on too long. If the game sounds interesting, you can head over to our Kickstarter page and read more details. I also just today posted a lengthy article comparing the features in Civ 5 to what I'm doing with ATG.
Let me know if you guys have any questions - happy to provide some answers!