This game is unique because it has a gameplay that can only be summed up as "RTS meets RPG meets TPS meets turn-based tactics".
You control, train, and equip a unit of soldiers fighting to liberate their small nation of Gallia from the invading forces of a much superior foe. Battles are played in turns that get determined by spending CP (short for command points, of which you get a limited amount per turn). You can control a soldier and move it on the field, but they will get fired on if spotted by an enemy, and can in turn fire on those enemies as well.
This makes for an intriguing mix that -- alongside a pretty nice plot -- makes for a very good and fun game. On top of it all, the Steam port is the best version of the game. So you should grab it.