Compiled and edited by Trevor Powell from postings to RGRN and spoilers written by Dylan O'Donnell and others. Corrections and additions can be sent to vulpine at zikzak dot net. A partial list of contributors has been included at the end of this spoiler. Thank you to all who have already sent corrections and things I'd forgotten about or hadn't been aware of. :)
HTML conversion by Kate Nepveu.
Last updated February 1, 2001.
In the interests of the hacking community at large (and due in large part to a conversation on rgrn), I've compiled a list of known insta-deaths within Nethack, coupled with known methods of avoiding said insta-deaths. Most or all of this information is probably already known to any Nethack veteran; this spoiler is intended to be used as a survival guide for the intermediate Nethacker who has learned to deal with floating eyes, and is now trying to survive against some of Nethack's nastier surprises.
For the purposes of this document, an insta-death is defined as a single move death which does not involve the player's hit points dropping to zero. (So for example, being killed by deadly poison is an insta-death, but being killed by the damage inflicted from regular poison is not an insta-death). For each insta-death, I give tips on how to avoid that particular hazard, and items that will help make each less likely.
I have also included a second section, 'Delayed Insta-Deaths' which covers causes of death which kill you instantly regardless of your hit points, but do so some period of time after some critical event occurs. For example, turning to stone because you ate a cockatrice corpse is an insta-death, but turning to stone a few turns after a cockatrice hisses at you is a delayed insta-death). For each type of delayed insta-death, I provide tips on how to avoid the hazard, as well as remedies that may be applied to save yourself during the delay between the event and the actual death. Of course, avoiding the hazard in the first place is always the preferred option.
Except where noted otherwise, all insta-deaths and delayed insta-deaths can be survived by wearing an amulet of life saving, so this preventative will not be listed in the individual entries.
Caused by trying to eat too much. Generally, when you try to eat too much, Nethack will warn you that you're "having a hard time getting it all down", and ask you if you want to stop eating. When asked this, it is highly recommended that you say YES. If you happen to finish eating at the same moment that Nethack would have asked you if you wanted to stop eating, Nethack will tell you "You're finally finished".
However, you won't get these warnings if you're already very full (which you are, immediately after either of the above situations). If you then try to eat anything -- even something as small as a fortune cookie or as insubstantial as a wraith corpse, you will choke and die instantly.
The moral of the story: Be extra-careful to give yourself time to digest your food before eating more food if you know you're nearly full! Take off your ring of slow digestion, if you're wearing one, to help in this process. (You don't want to be satiated for a long period of time anyway, as it will eventually cause your dexterity to drop). The smartest idea is to avoid being satiated as much as possible, and not to eat anything at all when you're feeling satiated.
Preventatives: An Amulet of Magical Breathing will keep you from choking on your food no matter what (though it won't save you from the other negative effects of being satiated). Wearing rings and amulets will make you digest your food faster, and will make it necessary to eat more often, so that you're less likely to choke to death if you're wearing lots of them (especially rings of hunger, regeneration, and/or conflict).. but will also increase your likelihood of running out of food and starving to death, or of fainting from lack of food at an awkward moment.
Being turned to stone can be caused instantly by catching sight of Medusa while she's alive, or by making direct flesh-to-flesh contact with a cockatrice/chickatrice; even a dead one.
Direct contact with a cockatrice includes attacking them bare-handed, kicking them if you aren't wearing shoes, picking them up or wielding them without gloves, stepping over their corpse while blind and not wearing gloves ("You try to feel what is lying here on the florr"), eating their corpses, being burdened and falling down stairs while wielding their corpses, falling into a pit while wielding their corpses, tinning them without gloves, sacrificing them without gloves, having a nymph or foocubus remove your gloves while wielding a 'trice corpse, trying to help one out of a pit without gloves, being polymorphed into a monster with a bite or a claw attack and attacking the cockatrice, and probably a bunch of other activities involving 'trices that haven't yet occured to me. In case the above hasn't made it obvious, I have to repeat that 'trices are DANGEROUS, even when long dead, and should only be handled if you're certain that there's no chance they'll come in contact with your bare skin. When in doubt -- run away!
Stoning can also occur in combat versus a live 'trice without direct flesh-to-flesh contact, when the cockatrice hisses. In this case, the stoning is a somewhat slower process, and so is not technically an 'insta-death'. Look in the delayed insta-deaths section below for information on 'stiffening' for further information on dealing with 'trices in combat.
In all other cases, stoning is instantaneous and irreversable; your only recourse is to practice prevention. Stoning by cockatrice is probably the leading cause of "Yet Another Stupid Death"s (although floating eye/newt combinations are a close second).
Preventatives: For 'trices, wear gloves and don't wield a 'trice corpse if you're burdened, or to be safer, only wield it while attacking; switch back to a different weapon before moving, lest you fall into a pit trap and turn to stone. If you do decide to wield a 'trice corpse, always double-check your burdened status before going down stairs, as attacks by xans, land mines, kicking sinks, and many other things can temporarily wound your legs and make you burdened. Poison can cause similar problems, and you may wind up burdened without noticing the change. For preventing Medusa's stoning ability, blinding yourself (by wearing a blindfold, for example) will keep you safe, as will possessing reflection (shield of reflection, silver dragon scale mail, amulet of reflection, etc.). While it might be reasonable to expect an amulet of unchanging to prevent the change to stone, this does not actually work.
Stepping into deep water (moats, puddles from a broken fountain, etc) may cause instant drowning if there isn't a square of land available for you to escape to (for example, if your potion of levitation wears off while you're floating over the middle of a lake).
Preventatives: Amulet of magical breathing to prevent the drowning. Wearing boots/ring of levitation or boots of water walking will prevent you from falling into water if you accidentally walk over it, but won't protect you from being grabbed and drowned by (;) monsters (see 'being pulled into a watery grave', under delayed insta-deaths).
Death rays are nasty, and you can never predict what enemy soldier might be packing a wand of death. A single zap hitting you means instant death, unless you're prepared.
The best defense is reflection. Not only will reflection stop the ray from affecting you, it will make the ray bounce back at the enemy who fired the ray, hopefully killing him in the process. Almost as good is magic resistance, which will simply nullify the effect of the death ray. If you have neither of these, your only hope is to either be invisible or to be wearing a cloak of displacement, either of which will give you some chance that your opponent will guess your position wrong, and so the death-ray will be fired away from you, which can buy you enough time to kill the bearer of the wand or to teleport away until you're better protected.
Preventatives: Magic reflection (typically silver dragon scale mail, amulet of reflection, or shield of reflection.) Magic resistance (typically Magicbane, grey dragon scale mail, or cloak of magic resistance), or being polymorphed into an undead monster will all protect you from the effects of a death ray. If your AC is below -17, you have a chance (albeit a small one) that the death ray will miss you.
This one falls squarely in the category of "Doctor, it hurts when I do this," except in two cases:
A frequent use of blessed scrolls of genocide is to kill mind flayers (for reasons discussed further below). Mind flayers have the symbol (h), which is also shared by hobbits, dwarves, and bugbears. If your character is a dwarf, even though you're represented on-screen by the symbol (@), you are actually an (h) in the game. If you're a dwarf and forget this fact and blessed-genocide the (h) class of monsters, you die instantly.
So don't do that!
Secondly, reading an uncursed scroll of genocide while confused will cause you to genocide your role (that is, your character type; if you're currently a valkyrie, then valkyries will be genocided). This, more than anything else, is the best reason not to read unidentified scrolls while confused!
Vorpal Blade has a 5% chance of beheading any target which possess a head each time it hits, with no way to defend against this attack.
Preventatives: Don't give Vorpal Blade to your pet (if your pet can wield weapons). Don't leave Vorpal Blade lying around where a monster might pick it up. If you must fight someone who has Vorpal Blade, either attack them from long range or polymorph into something which doesn't have a head. Obviously, attacking from long range is preferred, as polymorphing oneself into something without a head is a tricky business! If you must attack from close range without polymorphing into a headless creature, at the very least make your opponent go to sleep or be paralyzed before engaging in melee combat!
Each hit from the Tsurugi of Muramasa (Samurai class quest artifact) has a 5% chance of bisecting any target which isn't classified as a large target.
Unless you've done something unusual (like polymorphed yourself into a dragon), you're not a large target, and so have a 5% chance of death each time an enemy wielding the Tsurugi attacks you, exactly the same as Vorpal Blade, above.
Preventatives: See the above section on beheading, which applies equally here, except substituting polymorphing into a large monster for polymorphing into a headless monster. Again, attacking from a long range is the preferred option (since it's much easier than managing to polymorph oneself into a large monster!)
There are many instant-deaths possible with drawbridges. Two of the most common involve being crushed under the drawbridge while it's lowering, and standing on one when it's destroyed by the blast of a wand of striking or a force bolt spell.
Preventatives: Use caution. Whenever possible, destroy the bridge from afar and use levitation rather than cross it, and stay far (far!) away from them when they're closed.
Similar to a wand's death-ray, except without the ray, so reflection won't help you survive. Luckily, you're unlikely to meet anyone who uses the touch of death until very late in the game, so you have time to prepare yourself.
Preventatives: The only true defense against touch of death is magic resistance, or being polymorphed into an undead being, as described in the death-ray section, above. If you don't have magic resistance and have reason to believe that your foe may possess a touch of death attack, you need to kill that foe from a long distance, so they don't get in range for them to perform the attack! (note that most enemies which posess this attack are also able to teleport, so magic resistance is critical!) If you should happen to find yourself being attacked by a monster with a touch of death attack, except for Death or Yeenoghu then being in a state of hallucination will also protect you from the touch of death.
Well let's face it, this is just plain stupid. So don't do it!
Dungeon level 0 is considered to be nowhere. If you try to teleport yourself to that level, your body will be twisted and warped, and even an amulet of life saving won't save you! So don't do it!
Technically, you don't die if you do this and either have intrinsic flight or level-teleport to or beyond dungeon level -10, but it does immediately end the game without any chance of recovery -- not even an amulet of life saving will let you continue the game if you do this. Again, this falls into the category of don't do it! unless you are intending to escape the dungeon without successfully retrieving the Amulet of Yendor.
You've got lots of warning, here. Enemies which drain levels don't appear until the deeper parts of the dungeon, and you should be of a high level by the time you meet them (exception: kicking a sink can generate a succubus/incubus on any level of the dungeon, and they can drain levels. It is recommended that you not kick sinks until you're able to fully deal with succubi/incubi and the other perils which can be unleashed by kicking sinks. If you do find that you're having so many levels drained that you're in danger of dropping to level zero, escape back upwards in the dungeon to recover!
Defense: Wielding Excalibur, the Staff of Aesculapius, or Stormbringer will make you resistant to level-drain attacks (You may only want to wield these if you're of the appropriate alignment, however). Also, polymorphing into an undead or demonic creature will generally provide you with level-drain resistance. Having good magic cancellation will usually avoid the level draining effects (consult the armour spoiler for a detailed discussion of magic cancellation). If you have only a single level drained, you'll only require one experience point to regain that level. If you have multiple levels drained, one experience point will regain you the last level that was drained, and quaffing potions of full healing will regain you one level each, up to your original (pre-draining) level.
Mind flayers attack your intelligence directly ("The mind flayer's tentacles suck you! Your brain is eaten!"), which causes you to forget previously explored levels of the dungeon and identified items, and also drains your intelligence.
If your intelligence ever drops below 3, you die of brainlessness. Like the level drain above, you have lots of warning; if your intelligence drops very low in an attack against a mind flayer; run away! Remember that intelligence cannot be exercised like other statistics, so the only ways to raise it are: potions of gain ability, potions of restore ability, blessed potions of enlightenment, eating a mind flayer corpse, or repeated application of a unicorn horn. (Forgotten levels and objects will not be recalled by recovering points of intelligence)
An amulet of life saving will not save you from a death by brainlessness!
Preventatives: The most frequent solution is to blessed-genocide (h), so you won't ever have to worry about mind flayers again (But if you're a dwarf, see 'genociding own species' above for an important exception!) Alternatively, just be very careful to always wear a helmet (which will lower the likelihood of your brain being sucked out) and to teleport away if a mind flayer gets too close; mind flayers are best attacked with ranged weapons/spells! Wearing a dunce cap will lock your intelligence at six, which will protect you from deaths by brainlessness, but will also hamper your spellcasting unless you have a way to uncurse and remove it after you've killed the mind flayer. Wearing a ring of sustain ability will lock all your attributes at their current levels, and so will keep you from losing points of intelligence. Neither a dunce cap nor a ring of sustain ability will protect your memories of levels and objects from being sucked out, though!
This is the breath weapon of black dragons, and sometimes the weapon of choice for an extremely angry deity. A single hit will destroy a piece of your armour; if you have no armour, it will destroy the rest of you!
Preventatives: Blasts of disintegration count as ray attacks, so may be avoided in the same manner as any other sort of ray; magic reflection. Magic resistance will NOT help you against disintegration! Black dragon scales or black dragon scale mail will also grant you disintegration resistance. Eating a black dragon corpse will also grant you intrinsic disintegration resistance. Not praying to your deity when they're upset with you and not praying while in Gehennom (Vlad's tower doesn't count as part of Gehennom) will generally keep your own deity from deciding to send a disintegration blast at you.
Note that truly upset deities will frequently use wide-angle beams of disintegration, which even reflection won't counter! (true disintegration resistance will still protect you, however)
Poisoned needles in trapped doors or chests, spikes in pit traps, poisoned arrows, rabid rats, and many other poisonous items and attacks may not be simply poisonous (which reduce your strength, hit points, and hit point max), but deadly-poisonous (which will cause death instantly.)
Preventatives: Try to avoid pit traps; particularly those in the gnomish mines, which is where you're likely to find the highest concentration of traps (and thus, the highest concentration of spiked pit traps). Also try to kill rabid rats from a distance -- it's always possible that a single bite from a rabid rat will be poisonous, and that that poison will be deadly. Be careful with locked doors and boxes until you've got poison resistance. Watch out for mordor orcs (which frequently wield poisoned weapons). And most importantly, gain poison resistance as soon as you can; I recommend gaining poison resistance before entering the gnomish mines, where poison traps seem to be most common. Alternatively, you can play a class (barbarian, healer) or a race (orc) which begins the game with poison resistance, so you won't have to worry about this peril. Monks gain poison resistance at experience level 3, so they are also good choices for dealing with this danger.
For what it's worth, this is a relatively rare death. But that doesn't make it any less unpleasant when it happens to you.
Generally caused by food poisoning, but can also caused by the application of a cursed unicorn horn, or the touch of Scorpius, Juiblex, Demogorgon or Pestilence. "Ulch - that meat was tainted! You feel deathly sick." If your sickness isn't healed within only a few turns (approx. 10, though it varies), you'll die. If you're attacked with a sickness attack when already sick ("You feel even worse."), you'll die from your illness a few turns sooner.
Preventatives: Don't eat corpses which you didn't see die within the past few turns. (undead corpses are never truly safe to eat). You can also polymorph into a monster with sickness-resistance, if you really want to (most fungi are sickness-resistant).
Remedies: If you do become deathly sick, apply a unicorn horn (preferably blessed, for best likelihood of success, but definately not cursed), cast the Cure Sickness spell, eat a eucalyptus leaf, or quaff a blessed potion of healing, a non-cursed potion of full or extra healing, or a potion of holy water. If you can't do any of the above and you are in good standing with your deity (and above the valley of the dead), your deity will heal you if you #pray. Polymorphing will also save you from sickness, but is not recommended as a general purpose solution unless you really know what you're doing.
As mentioned above, if a cockatrice hisses at you in combat, you run the risk of slowly turning to stone. Similarly, if you eat an egg that was laid by a cockatrice, you'll slowly turn to stone. In both cases, when this happens, you have at least one turn to stop the stoning process, depending on how fast and burdened you are at the time.
Preventatives: Kill cockatrices from long range with spells or missile weapons. Note that you're much more likely to have the stoning process begin in combat if it's a new moon and you're not carrying a lizard corpse. So if it happens to be a new moon, be sure to carry a few lizard corpses around with you! (Nethack will inform you when you start or restore a game if it's currently a new moon)
Remedies: The usual method to stop the stoning process is to eat a lizard corpse. Since lizard corpses never rot, they're an important thing to pick up and tote along with you. Remember to keep them OUTSIDE of any containers you may be carrying things in, since you almost certainly won't have time to pull the lizard out of a bag AND eat it before you've turned into a statue! Quaffing a potion of acid or eating the corpse of an acidic monster will also save you from stiffening, as will the Stone to Flesh spell if you cast it at yourself (though it will also convert anything stone that you're carrying, including some rocks, rings, and wands..)
As mentioned under stoning, you might expect an amulet of unchanging to keep you from turning to stone, but this does not work.
By far the most frequent cause of drowning (discussed above) is being grabbed by eels or krakens (;), or by Couatls (A), and being pulled underwater. When you're grabbed by one of these monsters, you will get exactly one turn to save yourself before the monster pulls you into the water, drowning you as per the 'drowning' instadeath discussed above. (Note that if you're burdened or stressed, it is possible that you won't get to take an action during that one turn!)
Preventatives: Wearing an oilskin cloak or any greased armour will prevent (;) monsters from grabbing you, so they won't be able to drown you. Additionally, remember that in order to grab you, the monster must be able to hit you, so a low AC will greatly reduce your chances of being grabbed and drowned. Of course, blessed-genociding (;) will keep you from encountering eels and krakens. (A) cannot be genocided, however, so you mustn't let your guard down even if eels and krakens have been genocided!
Remedies: If you've been grabbed by an eel or kraken, you can save yourself by doing one of these actions on your single turn before being drowned: Kill the monster (in a single hit!), teleport yourself, teleport the monster (this can be done even on no-teleport levels), level-teleport, polymorph yourself into something that won't drown, or polymorph the monster, hoping it turns into something that won't drown you (which is a good bet). Alternatively, you can put on an amulet of magical breathing, to allow you to survive being pulled down into the water (this will lead to blanking potions and scrolls, though). As a last resort, it has been suggested that you zap a cold spell/wand at the eel or kraken, to try to freeze the water they're swimming in, so that they can't drown you within it.
Don't try to cross lava, even if you're heat-resistant and are wearing an amulet of magical breathing. You will become stuck in the lava, and unless you manage to pull yourself out in time, you will sink into the lava and die.
Preventatives: This is a "just don't do that" item. Stepping into lava is always a Bad Idea. If you must cross lava wear a ring/boots of levitation to avoid sinking into the lava. Alternatively, you can use a wand of cold or a frost horn to cool the lava so you can safely walk over it. If you have fire resistance, fireproof boots of water walking will allow you to safely walk over lava.
Remedies: If you do find yourself in lava, here's what you can do: Teleport. Zap a wand of cold (or any other sort of cold attack) downwards to freeze the lava, then apply a pickaxe or wand of digging downwards to dig your legs out of the frozen lava. Breaking a wand of cold will not only freeze the lava beneath you, but any adjacent lava as well. Putting on boots/ring of levitation will let you float safely over the lava. If they haven't been destroyed by stepping into the lava, boots of jumping will allow you to #jump out. If you can't do any of the above, then try to walk back out of the lava and onto solid ground; you may get lucky and manage to pull yourself out, but it's not guaranteed!
Green slimes (generally not seen outside certain parts of Gehennom) can slime you with their 'touch' attack. If you're slimed, you will slowly turn into another green slime over the course of several turns.
Preventatives: Always kill green slimes from a distance. Don't let them get close to attack you. (This implies that you should have some way to spot them from a distance) An amulet of unchanging will protect you from being slimed.
Remedies: If you get yourself slimed, you can pray to your god for help, if they're happy with you. Don't pray to your god, though, if you're beneath the Valley of the Dead (Vlad's tower doesn't count as being beneath the Valley of the Dead) or they'll become angry with you, so if you're beneath the Valley of the Dead, you'll need to teleport out of Gehennom in order for your deity to heal you. Additionally, putting on an amulet of unchanging will halt the sliming process. Reading a scroll of fire, casting 'Fireball' on yourself, zapping a wand of fire at yourself, stepping on a fire trap, lighting a potion of oil and throwing it upwards, and other methods of setting oneself on fire will burn the slime away (but will also hurt you and probably destroy many carried scrolls and potions at the same time). Casting 'Cure Sickness' on yourself or #invoking the Staff of Aesculapius will heal sliming more safely. Additionally, polymorphing yourself will heal you of sliming. Applying a unicorn horn will NOT stop sliming!
Thanks to all the rgrn readers who've contributed to this spoiler, including (but not limited to): Ray Chason, Chi, Sir Dies-A-Lot, David Goldfarb, Joseph N. Hall, Edward Jones, Tim Korvola, Jukka Kuusisto, Philipp Lucas, ManderRed, Russell Marks, Mooz, Dylan O'Donnell, okblacke, ptsc, Pekka Savlova, Raisse the Thaumaturge, Anthony Tong, StarChaser_Tyger, and Zack Weinber.