A magic candle is a SLASH'EM specific light source. It burns indefinitely but has no possibility of granting a wish, unlike a magic lamp. Also unlike a magic lamp, it can be wished for. It appears as a candle when unidentified.
It is easy to informally identify a magic candle. When lit, it has light radius 3 versus 2 for wax candles and tallow candles, and unlike ordinary candles, will not appear as partly used. Magic candles also cost much more than ordinary candles (250zm).
Magic candles are particularly useful for polearm and lance users (Yeomen and Knights), and those who prefer to use jumping boots. You cannot pound or jump to spaces you cannot see. Magic candles are preferable to magic lamps as permanent light sources because they are lighter and wishable, and the light radius is identical.
Unless there are not seven candles in the game – unlikely with the introduction of wax golems – do not attach these to the Candelabrum of Invocation. Doing so simply makes the candle mundane ("It looks very ordinary"), effectively wasting it; you cannot get an eternally-lit 4-square radius light source even if you attach 7 magic candles to the Candelabrum. You would get a slightly longer lifetime out of the Candelabrum (600 turns) by doing so, but this is hardly worth the multiple wishes that it would likely require.
Never used and used magic candles
A user has suggested improving this page or section as follows:
"Probably there is a usage fee!!!"
Interestingly, although magic candles never become "partly used", there seems to be a variable for whether a light source has been used at some point, which is still applied in the case of magic candles. This goes as far as not been able to be sold if ever used, like partly used candles. (shop owner: "seem uninterested"). Probably a little bug.
This means that a new magic candle will generally not stack with your old ones; however, once it has been lit at least once, it will. (Two groups of candles must be in the same state – lit or unlit – to merge, and obviously must meet the regular conditions like BUC status, same owner, and not unstably-polymorphed). This is pointless, however: unlike ordinary candles, having large stacks does not increase their light radius. In spite of this it is possible to wish for up to seven at a time, as with normal candles.
In Wizard mode you can't sell any magic candles, even not used. Used and not used still don't stack together. It's probably a bug.
The Candle of Eternal Flame
The Candle of Eternal Flame is the quest artifact for flame mages, conferring warning, teleport control, and cold resistance when carried. When invoked, it summons a tame fire elemental. It is neutral for wishing purposes. True to its name, it cannot be unlit, not even by water.