Smoky and milky potions
Smoky and milky potions are two of the randomly generated colors of potion; they can be any type. However, they are noteworthy because they have a chance of summoning a djinni and a ghost (respectively) upon quaffing. If either is summoned, you will not experience the potion's normal effect.
Quaffing a smoky potion has a 1/(13 + 2*djinn created in the game) chance of releasing the djinni. This djinni may be peaceful, may be hostile, or may grant you a wish. Djinn from blessed smoky potions have a 4/5 chance of granting a wish, djinn from uncursed potions have a 1/5 chance, and djinn from cursed potions have a 1/20 chance.
The effect of quaffing a smoky potion does not depend on whether or not you have identified that type of potion. If you have identified smoky potions but have forgotten which ones they are, you can use \ to check your current identification knowledge.
Also note: a djinni can be summoned when a monster quaffs a potion. The djinni will disappear 50% of the time; the other 50% it will be peaceful. In neither case will it grant wishes.
Chance of producing a djinni
|Djinn already created||0||1||2||3||4||5||n|
|Chance of producing a djinni||7.69%||6.67%||5.88%||5.26%||4.76%||4.35%||1 × 1/(13 + 2n)|
|Overall chance of wish||Blessed||6.15%||5.33%||4.71%||4.21%||3.81%||3.48%||0.8 × 1/(13 + 2n)|
|Uncursed||1.53%||1.33%||1.18%||1.05%||0.95%||0.87%||0.2 × 1/(13 + 2n)|
|Cursed||0.38%||0.33%||0.29%||0.26%||0.24%||0.22%||0.05 × 1/(13 + 2n)|
Milky potions behave similarly to smoky potions in that they have a chance of containing a ghost. The ghost will always be hostile, and unless you are blind when you quaff the milky potion you will be "terrified, and unable to move" for three turns. As with djinn, the probability of a milky potion generating a ghost is based on the number of ghosts already generated by any means. Since there will always be a large number of ghosts in the Valley of the Dead, the chance of getting a ghost from a potion decreases significantly after that point.
Smoky potions and wishing
Because of the possibility of a wish, it is worth blessing and quaffing all smoky potions, even if they are an otherwise useless or harmful type. In some cases, precautions must be taken; the table below outlines these cases and what can be done to mitigate their effects:
|sickness||50||20||Lose 1 hp, abuse Con||Quickly recovered|
|confusion||100||20||Confusion, abuse Con||Unicorn horn, or just wait (it's quite short)|
|invisibility||150||20||Permanent invisibility||Wear mummy wrapping|
|polymorph||200||20||Polymorph||Unchanging or polymorph control|
|acid||250||20||Lose 1-4hp, abuse Con||Acid resistance or recover|
|oil||250||20||abuse Wis||Quickly recovered|
Probably the worst of these is the potion of polymorph, since its effect is not easily resisted and can be quite devastating if proper precautions are not taken. Unchanging is preferable to polymorph control: controlled polymorph into your own race will shuffle your stats, while choosing to polymorph into another monster may keep your stats the same but will break polyselfless conduct. With unchanging, neither of these is an issue.
In the case of potions of sleep and paralysis, a locked closet with a burned Elbereth square or scroll of scare monster is a reasonably secure substitute: almost all phasing, digging or door-destroying monsters respect Elbereth, although the latter two may open the way for non-Elbereth respecting monsters. A sanctuary is an even better substitute, although still not as good as free action since As may still attack you.
Another problem can occur if smoky potions are potions of healing or extra healing. Since one will generally want to alchemize these to full healing, it poses a dilemma: get more HP, or get a wish? In this case, one should go for the alchemy - on average, for the potions required to get one wish, you will get 45 extra HP if smoky potions are extra healing, and 105 extra HP if smoky potions are healing. The extra HP is pretty much always better in the latter case, and usually better in the former case, especially given that many items can be obtained without wishing.
Both of these potions can be dangerous to use in tense situations. The milky potion effect is far worse, though: three turns of paralysis can be deadly against particularly nasty monsters, particularly if the potion was full healing. The smoky potion effect can also be dangerous, however, if your only potion of full healing instead produced a djinni, particularly one which did not grant you a wish, or worse, was hostile.
- potion.c in NetHack 3.4.3, line 364
- potion.c in NetHack 3.4.3, line 1949
- muse.c in NetHack 3.4.3, line 97