|Damage vs. small||1d3|
|Damage vs. large||1d3|
|Base price||60 zm|
There is a guaranteed luckstone in each of the three variants of Mines' End.
If you find a gray stone, DO NOT pick it up right away. First, make sure it is not a loadstone by kicking it; see the article linked above for more details). If it is, #name it on the floor (if you can) and leave it alone. If not, and you are an Archaeologist, you can safely use your own starting touchstone to identify it.
For non-Archaeologists, the second test is to rub it on an iron item: a touchstone will produce a "scritch, scritch" noise. Non-Archaeologists will want to keep a touchstone, as a blessed one is useful for identifying gems.
If both tests are negative, the gray stone is either a luckstone or flint stone. You should pick it up and type-#name it until you get two different kinds or have a chance to price-id it: luckstones cost 60 zm, while flint doesn't interest shopkeepers. If a monster with the attribute "likes magic" picked it up, it's not flint.
As long as you don't know whether it is a luckstone or flint stone, treat it as a luckstone. Luckstones are generated uncursed, so barring bones or bad Luck, they are safe to carry around.
A noncursed luckstone adds 3 Luck (which may exceed the ordinary maximum of 10) and a cursed luckstone subtracts 3 Luck. Luckstones carried in containers (e.g. bags) have no effect on Luck.
A cursed luckstone prevents the timeout of negative Luck, blessed ones prevent the timeout of positive Luck, and uncursed ones prevent both. For example, if you have a blessed luckstone and jump a lot in Sokoban, your total Luck will time out to three.
Multiple luck items have no cumulative effect. You get the blessed luckstone effect if you have strictly more blessed than cursed luck items in your open inventory, the cursed effect if the other way around, and the uncursed effect if you have equally as many blessed luck items as cursed (or all are uncursed).
You should formally BUC-identify your luckstone (i.e. via altar or scroll/spell of identify) as soon as possible so you can see when it gets cursed. Blessing it is not terribly important because there is no difference from an uncursed one as long as your Luck is not below its baseline value, though this makes it so it is not immediately cursed by spellcasting enemies.
A backup luckstone carried in a container or left in a stash may be useful in case your primary luckstone becomes cursed, assuming means of uncursing are limited; differently named, blessed luckstones in your inventory can help retain positive luck after facing a curse-slinging monster, especially in Gehennom.
Once you have a known luck item to prevent Luck timeout, you want to max out your Luck. This is a useful part of any ascension kit; do so ideally before you go to Gehennom. Good ways to increase your Luck are:
- Throwing precious gems to co-aligned unicorns; formally identified gems give 5 Luck each, while type-named ones give 2
- Sacrificing powerful monsters on a coaligned altar; you gain 5/24 of the value in Luck, and the value is usually equal to that monster's difficulty, with a few exceptions
Most players will want to keep their luckstone in their main inventory at all times once they have maxed out their Luck. However, if you don't mind the tedium and are very conscientious, it is somewhat safer to bag it and take it out only when it prevents Luck timeout: this is on turns divisible by 600, or by 300 if your god is angry OR if you are carrying the Amulet of Yendor (although you could just drop the Amulet).
There are notable exceptions to this max-and-keep Luck strategy:
- A cursed luckstone belongs in a container, as does any luckstone found on a bones level luckstone until you BUC-test it.
- If your Luck is below its baseline value, drop or bag all non-blessed luckstones every 600th turn (300th if your god is angry at you) until you fix it, or wait it out.
- Altar work requires Luck of at most 9 to avoid getting crowned when praying. The easiest way to control your Luck is to max it out, then lower it by breaking mirrors, squeezing onto a boulder or jumping in Sokoban, breaking eggs laid by you, or kicking a cross-aligned altar. Keep your luckstone, and watch those sacrifice messages!
- Blanking scrolls and potions by stepping into water becomes inefficient with high Luck.
In NetHack 3.4.3 and earlier (and some variants based on these versions), it was possible to determine if any given gray stone was a luckstone by trying to name it "The Heart of Ahriman" (the naming artifacts exploit). If the stone was a luckstone, your hand would slip and give it another name; if it was not, the attempt would succeed. This was fixed in NetHack 3.6.0: attempting to name any unidentified gray stone "The Heart of Ahriman" will fail, regardless of the stone's actual identity.
- This is 1 on full moons, -1 on Friday the 13th, 0 with both of the above, and 0 otherwise.