Slaves to Armok: God of Blood
Chapter II: Dwarf Fortress
Yes, it had to be made eventually...
Dwarf Fortress (also known as Slaves to Armok: God of Blood - Chapter II: Dwarf Fortress) is easily one of the most complex, robust, least hardware-demanding games ever made. Also, the hardest one to learn I ever recall....
What is Dwarf Fortress, essentially?
It is a mix of a strategy, simulator and roguelike game, with two (or three) game modes - a titular Dwarf Fortress mode, a less-likely-to-be-talked-about Adventure(r) mode, and also an indirect game mode, Legends.
In DF, you are given seven dwarves, with various abilities and labors (that you can customize pretty much), with basic equipment, you have to settle in one of (many) areas of your randomly generated world - it has its own history, civilization, wildlife and legends.
Once you settle (or embark, as referred to in-game) in a chosen location, you start to make your own dwarven fortress - here comes the"Strike the earth!", chopping down trees, making farms and many, many more aspects - from making stockpiles to maintaining water pumps to trading with other civilizations to making sure that your dwarves have enough food, ALCOHOL, and are happy - and there are many factors that can affect that - let it be noise made by workshops when one tries to sleep, purple, stenchy gases made by rotting flesh (miasma) to one's relatives not being buried or memorized - yes, your dwarves are not just mindless machines that do everything for you - they have to eat, sleep, they can have relatives that can "go past to the dawn of the time" - every single dwarf in your fortress has his very own, deep history.
This game's amount of content is so big that even after playing the game for a pretty long time you will always discover something new - let it be a new mineral, never-seen-before beast or a mysterious sickness causing vomiting and coughing blood...
The best part about that? The game is totally free to play. No fu**ing around with PayPal or other strange ways of transferring money - just go to the website (the title at the top of the post), download it and enjoy!
BUT, the creator(s) of the game highly appreciate donations, so go ahead and show your support for the land of "Slaves to Armok: God of Blood - Chapter II: Dwarf Fortress"...