I searched the forum, and didn't find anyone mentioning Dwarf Fortress from bay12games.

The game leads your first seven dwarfes to a mountain, and you're tasked to help them build a fortress under it. It's an economic simulation, but there is a small war part, where goblins invade (or if you piss the traders off enough, the humans or elves get angry too). So beware, and build traps, fortifications, train army dwarfes, build balisteas or catapults, train war dogs... Really, warring is only a small part as of now, see for yourself.

There's a second play mode in the game, which lets you wander the world (and your own constructions build in "fortress mode"). This is more of a rouge-like adventure game, which brings me to the graphics, or rather the lack thereof. Just look at the screenshots. Either you'll accept it, or you'll run, screaming and in fear.

Although the Interface is mostly intuitive, you won't get far without visiting the unofficial wiki. I have only played the game a few times, but the usual sitting time was more then 12 hours, so consider yourself warned.