If there was any series (scratch that, sub-genre) of titles that I wish I had more time to sit down and explore more thoroughly, it is the roguelike. I spent a lot of time with Rogue, Telengard, DND, and other such games when I was just a wee lad, and if not for real life challenging me for my time, I'd happily be exploring the more modern variants. But don't just take it from me, as there's this historical article on Gearfuse that goes into much greater detail about the strengths of the roguelike and why they're some of the most sophisticated games available despite their appearance.
Rogue was born of the desire of early computer programmers to recreate the experience of playing that nerdiest of early 80s pastimes — pen-and-paper Dungeons and Dragons — on a CPU that would be rejected today for being too underpowered by the manufacturers of the cheap calculator watches you can find in the prize belly of some midway claw machines. If you’ve ever raspingly breathed through your mouth loudly enough to have played pen-and-paper D&D, you’ll appreciate the difficulty of this. Dungeons and Dragons is a math-based game, in which the roll of a handful of polyhedral dice might be translated into the agile facility in which an elf ducks out of the path of a horde of rampaging gnolls… but the imagination behind the math is supplied by a person, the Dungeon Master, who controls and describes your adventure. In D&D, you’re rolling dice in the conjured worlds of a Dungeon Master’s imagination, and the fun for everyone lies in him describing how they fall.
The designers of Rogue saw that a computer could simulate D&D’s dice-based system well enough. It’s just math, and even the simplest computers do simple math well enough. Since the “graphics” of a game of D&D are supplied entirely by the player’s imagination, the rudimentary, text-only graphic capabilities of early 80s computers weren’t an issue either: this was a genre of game in which the player would not only accept but luridly imagine a lowercase ‘a’ as an ichorous, man-eating giant ant. The problem was simulating the Dungeon Master: that omniscient basement overnerd whose inexplicable whims could gelatinize a well-prepared group of adventurers just as easily as it could ascend into godhood the most unlucky and inept gaggle of bumblers this side of Icewind Dale. How do you emulate a living, breathing gameplay element that is both imaginative and capricious?
It’s estimated that about one in every thousand games of Rogue ends in a win, which makes the game far more capricious than the fantasies of even the most sadomasochistic and sociopathic Dungeon Master. Believe it or not, though, Rogue is a cakewalk compared to the rogue-likes it inspired. Nethack is probably the most famous of the lot. It adds a lot more of D&D inspired mechanisms to the rogue-like mix: for example, player classes. It also radically expands the number of weapons, armor-types, magics and monsters you face. But this is a disingenuously simplistic description of how radically Nethack alters Rogue‘s formula in both intricacy and capriciousness.
Rogue-likes form a genre of game that embraces the limits of what can be conveyed symbolically in ASCII text and turns those limits into strengths. By making a far greater assumption of a player’s imagination than most games — requiring that a gamer will imagine an azure equal sign to be a ring of frost, or turn a rouge semi-colon into a piranha, or a accept a lower-case p as a prancing pony, for example — rogue-likes free themselves of the development overhead that both suffer and limit other forms of video games. Money and man hours can be ignored. Rogue-like developers don’t have to draw, render, animate and give voice to every new monster, item, location or player action in their games; all they need to do is program it and assign it an alpha-numeric symbol.