Dwarf Fortress is a single-player fantasy game. You can control a dwarven outpost or an adventurer in a randomly generated, persistent world.

* The world is randomly generated with distinct civilizations spanning over 1000 years of detailed history, dozens of towns, hundreds of caves and regions with various wildlife.
* The world persists as long as you like, over many games, recording historical events and tracking changes.
* Command your dwarves as they search for wealth in the mountain.
* Craft treasures and furniture from many materials and improve these objects with precious metals, jewels and more.
* Defend yourself against attacks from hostile civilizations, the wilderness and the depths.
* Support the nobility as they make demands of your populace.
* Keep your dwarves happy and read their thoughts as they work and relax.
* Z coordinate allows you to dig out fortresses with multiple levels. Build towers or conquer the depths.
* Build floodgates to divert water for farming or to drown your adversaries.
* Play an adventurer and explore, quest for glory or seek vengeance.
* Meet adversaries from previous games.
* Recruit people in towns to come with you on your journey.
* Explore without cumbersome plot restrictions.
* Seamlessly wander the world -- up to 197376 x 197376 squares total -- or travel more rapidly on the region map.
* Accept quests from the town and civilization leaders.
* Retire and meet your old characters. Bring them along on an adventure with a new character or reactivate them and play directly.
* Z coordinate allows you to move seamlessly between dungeon levels and scale structures fighting adversaries above and below.
* The combat model uses skills, body parts, wrestling, charging and dodging between squares, bleeding, pain, nausea, and much more.
* A dynamic weather model tracks wind, humidity and air masses to create fronts, clouds, rain storms and blizzards.
* Over two hundred rock and mineral types are incorporated into the world, placed in their proper geological environments.
* Add new creatures, weapons, plants, metals and other objects via modifiable text files.
* Extended ASCII character set rendered in 16 colors (including black) as well as 8 background colors (including black).

It's a mod that adds orcs. Some people thought goblin sieges weren't painful enough.

Thread here.

I was under the impression that fortress mode was a secondary feature that got expanded because it was more fun than adventure mode

... And the users here have been playing DF way before you came here, anyways, ~35th fort, this'll be about testing some systems...

spend hours making an ascii statue out of glass or something.

I started watching Captnduck's tutorial series for it and playing along with him. So far it's been great. I've got a fresh fortress built into a hill of red sand.