So many games have followed in Rogue's ASCII footprints because, foremost, Rogue is fun. There's a lot of re-playability in the random generation of each level, treasure, and swing of the possible sword. Also, they are easy to create. There's a quasi-annual contest called the Seven Day Roguelike, in which various developers create a playable game in a week. If yours truly can write a sorta kinda maybe workable game, anybody can.
But even with such randomness within each game, the genre was growing stale. Crawl and ADoM are both excellent, innovative games--but if you've seen an white @ bump a red D for 2d6 damage once, you've seen it enough. GearHead took Rogue and added giant robots. I am firmly of the belief that giant robots make anything better, and this is no exception. But lately only one game has haunted my days and chilled my dreaming nights: Dwarf Fortess.
Dwarf Fortress lets you command a scrappy, half-trained band of dwarves out to form a new colony, delve deep into the mountains, and discover things better left undisturbed. The controls are not particularly intuitive, and you'll probably find that the first ten games or so are lost to some freak of the rules you didn't know (like "don't tease the mandrills" or "if you put that floodgate there you will drown" or "yes, dwarves do need to sleep"). One grits one's teeth are recites the mantra of the developer: Losing is Fun.
And by some intellectual sport of nature, it is. The first time your dwarves correctly take out the garbage, you'll cheer. They make friends, and pets, and take lovers. You control a great deal of their lives, but never them directly. They will disobey when they want; take a smoke break; get angry and break things; wander off; go mad. But they'll also build a surprisingly functional little community, if you guide them.
Anyway, if you are the compulsive type, as am I, I cannot discommend this game more. Prepare to lose sleep over it, wondering if your carpenter needs mangrove, specifically, or if any decent wood will do. If your Hammerlords can hold off the kobold archers until those useless Marksdwarves can get from the barracks to the Great Gate. If your sparkling stained glass window and elaborate sculpture garden will stop your dwarves from needing to go outside, where the elephants are waiting. Oh, Axe and Maul and Hammer, the elephants.