Roguelike games are two-dimensional dungeon-crawling computer role-playing games, named after the game Rogue from which they are descended. They are almost always set in a fantasy world, often derived from sources including myth, Tolkien and Dungeons & Dragons. Roguelikes usually use simple ASCII graphics; the hero is traditionally represented by an @ sign, while letters of the alphabet are used for monsters. A dog, for example, may be represented by the letter 'd', and a dragon by a capital 'D'. Items are shown as punctuation marks; a '?' typically represents a scroll and a '!' a potion. Some roguelikes have the option to play with 'tiles' where the ASCII characters are replaced by small pictures of the monsters and items.

Roguelikes are turn-based, meaning that even in the heat of combat, you can take as long as you like to plan your next move. (Many stupid deaths arise from people forgetting this and madly swinging at their opponents as though they were playing Quake.) Most roguelikes are single-player, because it would be hard to make them multi-player while still retaining their turn-based nature (imagine the situation where two players are in combat with the same monster). However, there are a few online multi-player roguelikes, such as Mangband (multiplayer Angband). Mangband is turn-based when only one player is on a level, but when multiple players are on the same level, it switches to allowing a fixed amount of time per turn. To help players with slow connections, your character will automatically fight back every round when in combat.

The hero is controlled by short commands of one or a few keystrokes rather than by typing long sentence-like commands. As roguelikes allow the hero to do a wide range of things (for example moving around, picking up and dropping items, reading scrolls, drinking potions, talking to monsters and casting spells) practically every key on the keyboard is used for something. Some roguelikes give you the option to use a mouse and select the commands from menus.

The appearance of magical items is randomised from game to game, and most dungeon levels are randomly generated, which gives roguelikes more replay value than games in which the levels and items are the same every time. Some roguelikes also feature static levels, such as a powerful demon lord's lair. Also, if a roguelike has a surface level (a wilderness or town), this usually has a fixed map.

Your character is described by a large number of stats similar to those used in Dungeons & Dragons. Two of the more important stats are HP (hit points, a measure of how much damage you can take before you die) and XP (experience points, usually gained by killing monsters). Experience points are important because when you have enough, you 'level up', which increases your HP and may give you more special powers. Levelling up is an important part of building up your character. Another important part is collecting useful items, especially magical items. For example, magical armour may be necessary to protect against the special attacks of some monsters, while wands can help you to kill them from a distance.

Traditionally in roguelike games, death is final and you only have one life (barring arcane magic such as the amulet of life-saving). The purpose of saving the game is to pause play until a more convenient time, not to be able to restart from the point where you saved. It is possible to evade this by making backup copies of your save file, but this practice is regarded as cheating.

History and Genealogy of Roguelike Games

Rogue, the game after which the genre was named, was written in 1980 by Michael Toy and Glenn Wichman with the intent of creating a game that they could enjoy playing themselves even though they knew exactly how it worked. They decided to have the Dungeons of Doom generated randomly each time, so that every game was a new challenge. They also used the then-new 'curses' library to display the dungeon levels as ASCII graphics, rather than giving long text descriptions of the hero's location, as most games did at that time. The objective was to head down to the bottom, get the Amulet of Yendor, and escape. Rogue was a very popular game which spawned a lot of variants and new games known as 'roguelikes'. A family tree of the best-known roguelike games can be found in this Guide to Roguelike Games, and a very comprehensive genealogy can be found at BALROG. Roguelikes are downloadable from the Internet at no cost, and most of them are open source, so that anyone can read the source code and make up new variants.

The list below is a genealogy of the most popular roguelikes. Games at lower levels on this list are 'descended' from games at higher levels. SLASH'EM, for instance, is a descendant of NetHack, which is a descendant of Hack, and all roguelikes are ultimately descended from Rogue. Games in bold are still actively played and developed.

Rogue (1980)

• Moria (1983)
  • Angband (1991)
    • Zangband (1994)
• Hack (1985)
  • NetHack (1987)
    • SLASH'EM (1996)
• Larn (1986)
• Omega (1987)
• ADOM (1994)
• Linley's Dungeon Crawl (1997)