Available on Steam for 19.99$, though it often goes on sale for less, Mount & Blade: Warband is a game that has offered me many, many hours of entertainment. The vanilla (slang for original, unmodded version) iteration of the game takes place in the fictional land of Calradia, during the early medieval ages.
One feature sets this game apart from others in its genre, however: No fantasy or magic. The technology is equivalent to the Middle Ages. There are six Kingdoms all constantly warring with one another, for land and power, in a confusing tangle of endless treaties and declarations of war. You get to pick your character and their background, which will influence you later in the game. You can ally yourself with a kingdom as a mercenary, or join as a noble and receive land, or the endgame for most players: Declare an independent kingdom and conquer all of Calradia, a feat that can take years in-game and months of real time.
Another feature that sets this game apart is the complex economic and political system: Your political prowess will depend on your relation with the lords and ladies of the land. Money makes the land of Calradia work, so if you wish for virtual power, you will also need lots of virtual denars, the fictional currency of the game. You can declare wars through military power, but also declare economic war by raiding villages and caravans.
What makes Mount & Blade: Warband truly special is the incredibly rich modding scene. These mods are set up by the developers to be very easy to download. Some are total conversion, meaning they change the setting of the game completely: From Feudal Japan, to the Napoleonic Wars, to Ancient Rome, and many, many others, it is hard to get tired with such a variety. With the countless mods available, even if you get bored with the game, you can simply install a totally different mod. The game also features a fantastic combat system, with four basic attacks (for most weapons) and four basic blocks, but you can also use a shield with a one handed weapon, which is easier to use, but can also break. The combat system takes some getting used to, but it is one of the more realistic combat systems I have seen (near the level of a simulator). The vanilla version and many mods feature multiplayer versions as well, where you can engage real players in combat.
A complaint of the game is the ‘alright’ graphics of vanilla singleplayer, as well as the monotony of vanilla singleplayer, although these can be fixed with the right mods.
Overall, it is a fantastic game, and if you are a fan of medieval times, or strategy games, then Mount & Blade: Warband is for you.
Empire is my game of choice for anything like this, just saying.