Myths and Facts about Nethack

Welcome to Eva's Nethack page! I noticed on the newsgroup rec.games.roguelike.nethack that several false rumours about the game frequently circulated and had to be debunked. I decided to create a web page dedicated to these myths about Nethack and the facts behind them. The information on this page has all been checked by source-diving and/or wizard-mode experimentation in Nethack 3.3.0 or later versions, and I believe that it is also correct for Slash'Em. Many thanks go to Dylan O'Donnell for the information on converting yourself that inspired me to create this web page in the first place, and for several corrections including alignment penalties for killing peaceful monsters. If you find anything wrong please email me.

Myths About Forbidden Actions

Changing alignment

MYTH: If you wear a helm of opposite alignment before the quest, your quest leader will not let you in, and your game will be unwinnable.

FACT: Simply remove the helm and you will be allowed on the quest again. A helm of opposite alignment only causes a temporary alignment change which is reversed when the helm is removed. (Since it takes away all divine protection, it's still not a good idea to wear one.)

If you convert yourself permanently (by sacrificing on a non-coaligned altar), then you will render your game unwinnable. You cannot convert back, and your quest leader will not be fooled by your wearing a helm of opposite alignment.

Under what circumstances will you convert yourself permanently? There is a myth about this too, and I am greatly indebted to Dylan O'Donnell for sorting me out.

MYTH: If your god is angry with you when you attempt to convert an altar, you will be converted to the altar's god instead.

FACT: If your god is angry but your alignment is positive, you can still convert altars. Your god will still be angry, but you can use the newly coaligned altar to mollify him.

You will convert yourself if you try to convert an altar when your alignment is negative, or if you sacrifice a unicorn of your own alignment on another god's altar.

MYTH: Unaligned altars (altars to Moloch) can't be converted; it is harmful to even try.

FACT: Unaligned altars in Gehennom cannot be converted. Unaligned altars outside of Gehennom, such as those on some quests, can be converted normally. It is, however, wholly impossible to convert oneself to Moloch.

Killing peaceful and tame monsters

There seems to be considerable confusion over the precise penalties for killing tame and peaceful monsters.

MYTH: Killing your pet will anger your god.

FACT: This depends on how you kill it. If you kill it in an ordinary way (e.g. in combat), you will ``hear the rumble of distant thunder''. The penalty will be -15 to alignment and -1 to Luck, but your god will not become angry.

If you kill it by displacing it into a trap or water, you will probably (75% chance) ``feel guilty about losing your pet like this''. If you do, then your god will become angry and you will also lose 15 points of alignment.

If you drown it by quaffing or dipping at a fountain or kill it with a scroll of genocide, there is no penalty.

The penalty for killing a peaceful monster is one or more of loss of protection, loss of telepathy, reduced luck and reduced alignment, depending on the type of peaceful monster killed.

  • Loss of protection is very rare as a penalty for killing peaceful monsters. It only happens if you kill a coaligned priest. (The commonest cause of lost protection is angering your god.)
  • Loss of telepathy is the penalty for killing a peaceful human if you're not chaotic. The message associated with this is ``You murderer!'' and you will also lose two points of Luck.
  • If you manage to kill a peaceful monster without angering it, you have a 50% chance of losing one point of Luck. This is in addition to the Luck penalty for murder described above and the penalty of -5 Luck for killing a unicorn of your own alignment. However, simply killing a peaceful monster with one whack from a melee weapon will anger it before it dies, avoiding this penalty. Most wands and spells will also anger a monster even if they kill it in one zap, but "beam" attacks such as striking or polymorph have a chance of killing without angering, and incurring the additional penalty.
  • Killing a peaceful monster tends to carry a large alignment penalty. If the monster is a type which is always peaceful (shopkeepers, priests, the Oracle, vault guards, watchmen and watch captains, quest leaders and guardians, prisoners, members of friendly races) the penalty is at least -15, except that there is no alignment penalty for killing peaceful priests of Moloch. If it is peaceful because it is coaligned, the penalty is at least -9. These penalties only apply to monsters created peaceful, not ones which have subsequently been made so.

Quest friendlies cause you to lose vast amounts of alignment, coaligned priests carry a penalty of only -2 but should probably not be killed because of the loss of protection, cross-aligned priests carry a small alignment bonus, and priests of Moloch carry a large alignment bonus. If the monster is still peaceful when it dies (as mentioned above, this is unlikely), there is an additional penalty of -5, unless it was a quest leader or guardian or a priest.

Killing, eating and sacrificing your own race

  • Regardless of your race, killing a peaceful human will cause you to lose telepathy unless you are chaotic. Killing a peaceful elf, dwarf, gnome or orc will not. Killing a coaligned priest will also cause you to lose all your protection, even if you are chaotic.
  • Eating your own race is cannibalism and will give you permanent aggravate monster and lower your luck unless you are an orc or Cave(wo)man (or, in Slash'EM, a Lycanthrope or Vampire).
  • Unless you are chaotic or polymorphed into a demon, sacrificing your own race is a very bad idea.
  • It's fairly obvious what monsters count as dwarves, gnomes, elves or orcs, but working out what is and is not human can be a bit trickier. Anything represented by an @ sign that isn't obviously an elf is human, including werecreatures and doppelgangers. Keystone Kops (anything represented by a K) are also human.
  • Slash'EM players should note that Elves and Drow are the same species, and that if you are a Doppelganger you are racially human and should not eat human corpses. Orcish, lycanthropic and vampiric players are not punished for eating or sacrificing their own race, but for completeness, here's how it works for them:
    • Anything represented by an o is an orc, including goblins and hobgoblins.
    • Only lycanthropic monsters (were-things) are classified as the same race as lycanthropic players. I.e., a Lycanthrope will not feel evil and fiendish when eating a human, only when eating another lycanthrope.
    • A Vampire will only feel evil and fiendish when eating a vampire bat, a fire vampire or a star vampire. Since these last two are not undead humans but Lovecraftian monsters, it is probably a bug that eating them counts as cannibalism. Vampire corpses would also have this effect, but they don't exist - vampires, and their lords and mages, leave an old human corpse when killed.

Alignment differences

MYTH: Prayer timeout is quicker for lawfuls than for chaotics.

FACT: Prayer timeout behaves exactly the same way for all alignments. The myth derives from a bug in Nethack 3.1.3 which caused it to be longer for crowned chaotics.

MYTH: Lawful characters must not rob shops / attack peaceful monsters / eat while satiated / ....

FACT: There are assorted actions (such as robbing shops) for which lawfuls receive a -1 alignment penalty and chaotics receive a +1 alignment bonus. There are other actions (such as eating while satiated) for which only Knights or Samurai are penalised. These class/alignment specific penalties are very minor and can usually be safely ignored. The alignment penalty for killing peaceful monsters is more severe, but applies to all characters. For details of all actions which affect your alignment, see the Appendix to Matthew Lahut's Praying Spoiler.

Keys in Minetown

MYTH: It's safe to unlock doors in Minetown with a key in full view of the watchmen.

FACT: The watchmen will still warn you and then get angry if they notice you doing it. Usually they don't, because unlocking a door with a key normally only takes one turn, while a lock pick or credit card takes longer.

Carrying cockatrice corpses

MYTH: If you fall into a pit while carrying a cockatrice corpse, you will turn to stone.

FACT: Falling will only turn you to stone if you are actually wielding the corpse. For details on all the ways in which cockatrices and their corpses can petrify you, see David Corbett's cockatrice spoiler.

Other Myths

Altars

Dropping items on altars to see whether they are blessed or cursed works with an altar to any god, even Moloch, although obviously you must not be blind or hallucinating at the time. You can also buy protection from any peaceful priest who is still in a temple of his or her own alignment, even the priest of Moloch in the Valley of the Dead. (Slash'EM players should note that despite appearances, the altar room on the Nightmare level is not a temple, so you cannot buy protection from the priest there.) Dylan O'Donnell's spoiler collection includes more information on donating to priests.

By the way, altars and priests are ``coaligned'' if they are of the same alignment as you, ``non-coaligned'' or ``cross-aligned'' if they are of a different alignment, ``aligned'' if they are lawful, neutral or chaotic, and ``unaligned'' if they are of Moloch. Unaligned altars do not appear in the main dungeon, only in Gehennom and some quests.

Wands of cancellation

Wands of cancellation are not as dangerous as many people imagine, provided that you are careful not to put a charged one into your bag of holding.

  • In vanilla Nethack, the only way to get your entire inventory cancelled is to zap yourself with a wand of cancellation or break one deliberately. A wand of cancellation exploding for any other reason, such as being hit by lightning, will not cancel your inventory. In Slash'EM, an exploding wand of cancellation will cancel your inventory, so I keep mine in a sack when not in use. Also, in Slash'EM but not vanilla Nethack, monsters can zap you with wands of cancellation. When this happens, each item in your inventory has a 1/24 chance of being cancelled. Magic resistance provides complete protection against this.
  • Although being cancelled is nasty, it only affects your equipment - you do not lose any intrinsics.
  • Cancelling a bag of holding makes it into an uncursed bag of holding and does not affect the contents. Great for bones piles which include a cursed bag of holding full of useful equipment.
  • Cancelling the blessed rustproof +6 Mjollnir makes it into the uncursed rustproof +0 Mjollnir. Probably only of interest to those who are determined to enchant their artifact weapon to +7.
  • Irina Rempt has written an excellent spoiler explaining everything you could wish to know about cancelling objects.

Holy and unholy water

Items dipped into holy or unholy water will not blank, dilute, rust, get wet, or suffer any type of water damage. They will simply be blessed or cursed as appropriate. Items dipped into uncursed water will suffer the typical effects of getting them wet.

Training your pets

MYTH: If you pick up corpses and drop them before letting your pet eat them, it will keep it tamer.

FACT: Your pet's apport, or willingness to fetch, can be improved by feeding it personally. However, only treats will work for this purpose, and corpses aren't treats. Tripe rations and meatballs are treats for a dog. Apples and carrots are treats for a horse.

Your pet's tameness, or resistance to going wild, increases whenever it eats, whether you've touched the food or not.

I have written a spoiler with more information about apport and tameness, and Peter Snelling, Boudewijn Wayers and Bryan Butler have written a detailed spoiler on training pets to steal.

Invisible pets

MYTH: If you can see invisible, it's a good idea to make your pets invisible.

FACT: This is only applicable to steeds. Invisibility has no effect on monster-vs-monster combat, but if your steed is invisible, monsters will attack you rather than it more often. Whether this is a good or bad thing depends on how strong you are and how much you care about keeping your steed alive.

Vulnerability to nymphs

MYTH: Female characters are less vulnerable than male characters to nymphs.

FACT: Although Nethack has nymphs "seduce" males and "charm" females, the difference in the messages is purely cosmetic and your gender has no effect on your vulnerability to nymphs.

Time and date effects

MYTH: If you start a game during a new moon, your base luck will be -1.

FACT: New moons have no effect on your base luck. The only effect they have is that cockatrices are slightly more dangerous. There is a one-point luck penalty for starting or restoring a game on Friday the 13th, and a one-point luck bonus for starting or restoring during a full moon (these can cancel each other out). Boudewijn Waijers and Dylan O'Donnell have written a spoiler giving full details of the effects of time and date on the game.

Gaining intrinsics

MYTH: Get teleportitis before eating a tengu because then it's more likely to give you teleport control.

FACT: When you eat a monster which can grant multiple intrinsics, first the intrinsic it will try to grant is chosen at random without reference to your current intrinsics, and then it is determined whether or not it will be granted. Of course, it can only be granted if you don't already have it.

Eating rings

MYTH: Eating a ring of increase damage for the intrinsic will permanently increase your food consumption.

FACT: Eating rings or amulets does not normally increase food consumption (unlike wearing them). The exception is that gaining intrinsic regeneration, conflict or hunger by eating a ring will raise your food consumption by one point every two turns (normal food consumption is one point per turn).

On the subject of rings and food consumption, there is no point in constantly wearing two rings of slow digestion. With one, your food consumption is reduced to 1 point every 20 turns, but with two, it is 1 point every 10 turns, because both rings are causing their "ring hunger" effect. Because of the details of when ring hunger is checked for, it is possible to reduce your food consumption to zero by wearing two rings of slow digestion most of the time but removing each one just before it would cause its hunger effect and replacing it afterwards.

Dylan O'Donnell has written a spoiler on food which includes a list of all factors which affect food consumption.

Excalibur

MYTH: Getting Excalibur is easier for Knights than for any other class.

FACT: Any lawful character of level 5 or higher has exactly the same chance of getting Excalibur by dipping. Excalibur used to blast non-Knights in version 3.3.1, but this bug was fixed in 3.4.0.

MYTH: Excalibur is the Knight's first gift from sacrificing.

FACT: Actually, it cannot be obtained by sacrificing at all, nor can it be generated randomly.

Learning spells

MYTH: Your spellcasting stat (Intelligence or Wisdom, depending on your class) affects your chance of learning spells.

FACT: No matter what class you are, Intelligence affects your chance of learning spells and Wisdom does not. The spellcasting stat applies to the chance of casting spells successfully.

Casting forgotten spells

MYTH: Confusing yourself with a forgotten spell is less useful in Nethack 3.4.3 than it used to be, because it might stun you as well.

FACT: It's true that forgotten spells can stun you, but you can simply apply your unicorn horn and try again until you are confused but not stunned. Also, being stunned prevents teleport control from working but does not affect the results of reading any scroll apart from teleportation.

The Vibrating Square

MYTH: The Vibrating Square will move if you drop an object on it or dig down while standing on it.

FACT: The Vibrating Square will never move and cannot be destroyed. Also, it cannot be generated inside a wall or on a trap, although it can be generated under an object. You will feel a strange vibration under your feet whenever you move onto it. This happens whether you walked onto it normally or (level-)teleported there. Even if you are levitating, flying or riding, you will still feel the vibration.

Keeping your experience level low

MYTH: Keep your experience level low so that the monsters you encounter while climbing up with the Amulet and in the Elemental Planes will be less dangerous.

FACT: The upper limit on the difficulty level of randomly generated monsters is normally the average of your experience level and your current dungeon level. Once you have the Amulet of Yendor, however, the upper limit increases to the average of your experience level and the dungeon level of Moloch's Sanctum. (There is also a lower limit, but this depends only on the depth of Moloch's Sanctum, not on your XL.) Moloch's Sanctum can never appear above DL:45, and a post-quest character will have at least XL 14 unless they have deliberately level-drained themselves.

The randomly-occurring monster with the highest difficulty level is the arch-lich, at 29. To avoid meeting them, one would need to have XL 12 or less (assuming the shallowest possible depth for Moloch's Sanctum). Most people avoid them by genociding them instead. The second most difficult monster is the Archon, at difficulty level 26, and one would need XL 6 or less to avoid them.

Although the rules for generating monsters of a fixed class are different (monsters of more than twice your XL are less likely to be generated but can still appear), the only place this is likely to cause trouble on the ascension run is the Astral Plane, and then only if master liches and arch-liches have not been genocided.

The Wizard's reappearances

MYTH: The Wizard of Yendor will reappear one final time when you enter the Plane of Earth, and will never come back again once you've killed him there.

FACT: He can reappear on any of the Elemental Planes after being killed on the Plane of Earth, but he cannot appear on the Astral Plane.