Digestion

This article is about the damage type. For the item in SlashTHEM, see bag of digestion.

Digestion is a damage type that occurs in NetHack, and is only used for specific engulfing attacks.

Description

The following monsters have engulfing attacks that digest their victims:

• t lurker above
• t trapper
• w purple worm

Digestion attacks have different effects depending on if the target is the hero or another monster.

Against the hero

If a digestion attack hits the hero and engulfs them, a delayed instadeath begins: while they are engulfed by that monster, they will continue to take damage on each of that monster's turns, which abuses strength and is accompanied by messages about being digested—each hit that brings the hero within 2 hits or closer to total digestion prints a slightly different message, and instadeath occurs when that count reaches zero. To survive this, the hero must escape or kill the engulfing monster before it fully digests them; as with other engulfers, the hero's melee attacks, spells and wands are guaranteed to hit that monster. Being hit by a digestion attack while riding will also forcibly dismount the hero from their steed.

The better the hero's constitution and AC are, the longer that they will take to be fully digested—the number of monster hits required is calculated with the following equation:

$8 + \frac{Con}{3} + d(\frac{25 - monsterLvl}{2} + 1) - AC$

Digestion can be completely prevented by wearing a source of slow digestion (i.e. the ring), which causes a monster to immediately regurgitate the hero without any damage being dealt. Zapping a wand of opening or casting the spell of knock will force the monster to spit out the hero, while zapping a wand of digging or dig spell while inside them will reduce its HP to 1 and force it to immediately expel the hero. Reading a scroll of taming or casting charm monster limits the effects to the monster engulfing the hero, and a monster pacified or tamed this way will regurgitate the hero.

A hero polymorphed into a web-spinning monster can use the #monster extended command while being digested to force the monster to spit them out. A hero that hits a monster digesting them with a stoning attack (e.g. a footrice corpse, or attacking while in the form of one) will turn them to stone and escape from its statue, unless they have stoning resistance. A hero that polymorphs into a monster form that is huge or larger will force the monster to regurgitate them.

If the hero is wearing an amulet of life saving and is totally digested, or else is in explore mode or wizard mode and chooses not to die, they will be revived as normal and regurgitated. This also applies if the hero are fully digested while polymorphed, which returns them to normal form and causes the monster to spit them out.

The following information pertains to an upcoming version (3.7.0). If this version is now released, please verify that the information below is still accurate, then update the page to incorporate it.

White dragon scales and white dragon scale mail also confer slow digestion.

Against monsters

Against monsters, digestion attacks will instantly kill monsters of large size or smaller, with life saving causing them to be regurgitated if it triggers; larger monsters are unaffected. Monsters killed this way do not leave corpses, and death drops that rely on a corpse being left (e.g. unicorn horns) will not be generated. A monster that kills another monster by engulfing them gains half the nutrition value of their corpse and will be immobile while eating for ¹⁄₄ of the normal duration.

A monster that swallows a chameleon whole with a digestion attack will polymorph, including a hero in the form of one; a worn source of protection from shape changers will prevent a monster from polymorphing this way. Attempting to digest a footrice or Medusa will petrify the engulfing monster unless they have stoning resistance, while attempting to digest a Rider will kill the digesting monster instead and leave the Rider unharmed.

If the hero is polymorphed into a digesting monster, killing a monster of the hero's race using a digestion attack is not considered cannibalism.

Strategy

Though a potential source of instadeath, players that encounter monsters with digestion attacks are typically more than capable of escaping such a fate. Purple worms are the fastest monsters with a digesting attack, making them the most threatening to deal with on paper; lurkers and trappers have a much slower speed of 3. In practice, a player encountering a digesting monster will generally be well-equipped and at worst have a wand of digging to escape with, unless the monster was a purple worm summoned by an early shrieker. As being engulfed guarantees that melee attacks and spells will hit the engulfing monster, even a hero with modest speed and damage output can likely finish them off before the instadeath occurs.

Digestion attacks are a particular concern with pets: a single hit from a lowly trapper can fell an Archon among other powerful pets that are small enough to be eaten. A character relying primarily on their pets to do damage (e.g. a pacifist) wants to be particularly cautious of all digesting monsters. Conversely, this is what makes the purple worm in particular a very powerful pet: it can immediately eliminate most high-threat-level monsters if they are small enough, and can rapidly gain levels by swallowing wraiths whole, though they will encounter trouble against common monsters that are too large to engulf such as the various giants. While trappers and lurkers above can do the same as purple worms, their low speed and tendency to hide makes them generally impractical as pets.

The following information pertains to an upcoming version (3.7.0). If this version is now released, please verify that the information below is still accurate, then update the page to incorporate it.

Per commit cf1c7251, shriekers will summon baby purple worms instead of adult ones if they are in an area where the latter is out of depth.

Per commit 1a2d844a, digestion will not affect incorporeal monsters such as wraiths.

History

Digestion is introduced in Hack for PDP-11, which is based on Jay Fenlason's Hack, with the addition of the lurker above, trapper and purple worm—all three monsters are included in the initial bestiary for Hack 1.0.

In NetHack 3.6.1 and previous versions, including some variants based on those versions, if the hero is being digested by a monster and life saving is triggered by some other cause of death, they will be totally digested and killed on the next hit from the digestion attack; this bug is fixed in NetHack 3.6.2 via commit 858e9ce0.

Messages

<The monster> lunges forward and plucks you off <your steed>!

A monster landed a digestion attack while you were riding.

<The monster> digests you!

You take damage from digestion.

<The monster> thoroughly digests you!

You take damage from digestion, and will die in 2 more hits.

<The monster> utterly digests you!

You take damage from digestion, and will die in 1 more hit.

<The monster> totally digests you!

You died from being digested.

<The monster> opens its mouth!

You zapped a wand of opening or the knock spell while being digested.

You feel a sudden rush of air!

As above, while blind.

You pierce <the monster's> <stomach> wall!

You get expelled from <the monster> with a squelch!

You zapped a wand of digging while being digested.

You get regurgitated!

The monster trying to digest you spat you out.

Obviously <the monster> doesn't like your taste.

This is added if you were immediately spat out due to a worn source of slow digestion.

<The monster> very hurriedly regurgitates you!

You were expelled due to life saving activating after being digested.

Brrooaa... You land hard at some distance.

This is added if you are placed more than one square away from the monster after it spits you out.

You <jump/fly> through an opening in the new statue of <the monster>.

You turned a monster that was digesting you to stone.

The following information pertains to an upcoming version (3.7.0). If this version is now released, please verify that the information below is still accurate, then update the page to incorporate it.

As of commit beb99c0, there are different messages that distinguish between animals that engulf you (which covers all digesting monsters) and other monsters:

<The monster> <lunges forward and> swallows you whole!

You were engulfed by a purple worm.

<The monster> <lunges forward and> encloses itself around you!

You were engulfed by a lurker above or trapper.

"Burrrrp!"

A monster with a digesting attack (including you if you are polymorphed into a monster with one) killed another monster by digesting them.

Unfortunately, digesting any of it is fatal.

While polymorphed, you tried to digest one of the Riders.

<The monster> belches feebly, shrivels up and dies!

A monster with a digesting attack tried to eat Famine.

<The monster> coughs spasmodically and collapses!

As above, with Pestilence.

<The monster> vomits violently and drops dead!

As above, with Death.

Variants

Variants of NetHack may give digestion attacks to new or returning monsters and adjust or expand the attack's mechanics.

SLASH'EM

In SLASH'EM, digestion attacks will not instantly kill monsters if the target needs an enchanted weapon to hit and the attacker does not hit as a strong enough weapon. This makes pets with enchantment resistance much more capable of surviving against purple worms and other digesting monsters.

All of the above information also applies to SlashTHEM.

GruntHack

In GruntHack, dragons can digest monsters and the player, making them much more difficult to fight in melee - this also makes them much better pets compared to vanilla NetHack.

dNetHack

In dNetHack, more monsters are given digestion attacks:

• t metroid queen
• P darkness given hunger
• t mouth of the goat
• U Grue
• U shambling horror (randomized)

notdNetHack

In notdNetHack and notnotdNetHack, in addition to dNetHack details, Ahazu also possesses a digestion attack.

EvilHack

In EvilHack, dragons are capable of digesting monsters as in GruntHack, making them fearsome enemies and desirable pets. Shambling horrors can also roll digesting attacks among their randomized attack routine.

Monsters will wear the ring of slow digestion, which prevents them from being digested and instantly killed; spiked barding and Ithilmar can also prevent the monster wearing it from being digested. Phasing prevents you or any monster with the property from being engulfed at all.

Some of the stronger monsters in the game are generated with a ring of slow digestion - this includes player monsters on the Astral Plane in order to weaken "purple rain" and other similar strategies for trivializing the level.