Cthangband, by Dean Anderson and David Thornley, is a variant of the roguelike game Angband, based on the Cthulhu Mythos of H. P. Lovecraft. Originally a code fork from Zangband, Cthangband develops both the setting and the game mechanics of Angband in directions quite different from most variants.

Cthangband is set in the Dreamlands, the mystical dream-realm of Lovecraft's The Dream-Quest of Unknown Kadath and "Celephais". The setting is rather more complete than the Middle-Earth of original Angband or the Zelaznian Amber setting of Zangband. Almost all the locations in the game -- towns, dungeons, and so forth -- are landmarks from Lovecraft's Dreamlands. Beautiful Celephais and dark Dylath-Leen are there; as are the foulness of Koth and the utmost fastness Kadath of the Gods.

In terms of game mechanics, Cthangband strikes out on its own from the very beginning. While there are the usual multiplicity of races, there are no character classes. Instead, there are "templates" -- which provide a character with initial skills and equipment, but none of the restrictions usually implied by character class. A character begun as a Mage may develop unrestricted fighting prowess; a Swashbuckler or Gladiator may study magic.

There are also no experience levels. Instead, characters gain power by practicing numerous skills -- weapon proficiencies, types of magic, and so forth. To bring up your character's hit points, don't bother slaughtering lots of monsters to gain level. Instead, let your character take damage (and then heal it); this trains your Toughness skill. Such is the logic of the Dreamlands. Skills are measured in percentages, and become increasingly hard to improve as they go up.

It seems like every Angband and Nethack variant rewrites the magic system. Cthangband is no exception. To the basic Angband magic system -- known here as "hermetic magic" -- there are three additions: hedge magic, mindcrafting, and shamanism. Hedge magic, which uses small, portable objects known as charms, is quick to learn, but limited in power. Mindcrafting, a form of psionics, is demanding but has potent high-level effects. Shamanism replaces Angband's clerical prayers; it relies on the binding and invocation of spirits and is an unreliable mixed bag -- but is the only source of healing spells.

Perhaps disappointingly for those familiar with Chaosium's Call of Cthulhu game, there is no SAN (sanity) score.

As with most Angband variants, Cthangband is portable, and has been ported to multiple platforms, including Unix, Linux, Win32, Mac OS, and Amiga. You can download Cthangband from David Thornley's Web site, http://www.visi.com/~thornley/david/cthangband/, or from Thangorodrim at http://thangorodrim.angband.org/.

Update, June 2002: Cthangband has forked! Due to a lack of time, David Thornley has not been maintaining Cthangband very actively of late. One of its other contributors, Kieron Dunbar, has forked his own version, sCthangband, with several enhancements particularly in character generation. sCthangband can be had from Thangorodrim.