Impurity - Revision history

Umbire the Phantom: pothole

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Umbire the Phantom: potholes

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Klepto: added strategy section.

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In the context of [[dNetHack]], [[notdNetHack]], and [[notnotdNetHack]], [[impurity]] refers to a mechanic that keeps track of tainted or unclean actions performed over the course of the game. It is primarily used by [[chaotic]] Undead Hunters and other students of [[defilement]] but is kept track of for any character. Impurity is gained either by performing—or being subject to—certain spiritually immoral actions. Whether you are victim or perpetrator does not matter; both are tainted.

==Description==
There are the 23 categories of exposure, each corresponding to a different set of unclean actions and a corresponding counter that increases every time they are performed. Whenever that counter reaches 1, 4, and 15, that category's impurity score ticks up by one, with most categories allowing at most 3 points of impurity to be gained. When an impure action is performed, there is a {{sfrac|impurity}} chance of increasing the current counter, which translates to needing only one exposure for the first point, roughly 7 for the second point, and around 120 exposures for the third.

The "Great Old One transcendence" category instead allows up to 6 points to be gained, with the first three exposures being guaranteed to increment the counter, and subsequent exposures only having a one-in {{sfrac|transcendence|2}} chance of incrementing the counter.

{| class="wikitable"
|-
!scope="col"| ||colspan=15| Odds
|-
!scope="col"| Impurity
|scope="col"| 0 || 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13 || 14
|-
!scope="row"| Chance
| 100% || 100% ||{{frac|2}} || {{frac|3}} || {{frac|4}} || {{frac|5}} || {{frac|6}} || {{frac|7}} || {{frac|8}} || {{frac|9}} || {{frac|10}} || {{frac|11}} || {{frac|12}} || {{frac|13}} || {{frac|14}}
|-
!scope="col"| ||colspan=15| Odds
|-
!scope="col"| Transcendence
|scope="col"| 0 || 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13 || 14
|-
!scope="row" | Chance
| 100% || 100% || 100% || 100% ||{{frac|2}} || {{frac|2|5}} || {{frac|3}} || {{frac|2|7}} || {{frac|4}} || {{frac|2|9}} || {{frac|5}} || {{frac|2|11}} || {{frac|6}} || {{frac|2|13}} || {{frac|7}}
|}

===Categories of impurity===
{| class="wikitable"
! Impurity !! Causes !! Thresholds (points)
|-
| Meat || Eating meaty corpses: any that would break the vegan and vegetarian conducts count for this. || 1, 4, 15 (3 pts.)
|-
| Blood || Hitting with—or being hit by—[[AD_VAMP|vampiric attacks]], quaffing blood, scrawling in blood as a vampire, attacking with the alternate form of the [[chikage]], [[Phlebotomy kit#Description|drawing]] and transfusing blood. || 1, 4, 15 (3 pts.)
|-
| Bodies || Picking up corpses, being attacked by [[skeleton]]s or [[zombie (dNetHack)|zombie]]s. || 1, 4, 15 (3 pts.)
|-
| Death Magic || Using or being hit by death magic or draining magic: [[wands of death]], [[finger of death]], the [[touch of death]] monster spell, the [[Spellbook of drain life|drain life spell]], and [[wand of draining|wands of draining]]. Still applies if you resist or survive. || 1, 4, 15 (3 pts.)
|-
| Great Old One Transcendence || Witnessing a [[Great Old One]] survive death. || 1, 4, 8, 16, 32, 63 (6 pts.)
|-
| Theft || Having your items stolen or using stolen items. Stealing a monster's items: natural theft attacks, wages of greed, dolls of stealing. || 1, 4, 15 (3 pts.)
|-
| Murder || Killing monsters of any type that are both peaceful and intelligent, including, but not limited to, [[murder]]. || 1, 4, 15 (3 pts.)
|-
| Bloodlust || Lowering your [[alignment record]], e.g., reading golden scrolls of law. || 1, 4, 15 (3 pts.)
|-
| Graverobbery || Digging up [[grave]]s. || 1, 4, 15 (3 pts.)
|-
| God Anger || [[Anger]]ing or getting [[smite]]d by any god. || 1, 4, 15 (3 pts.)
|-
| Illness || Being affected by [[illness|severe illness]] or [[food poisoning]]. || 1, 4, 15 (3 pts.)
|-
| Dirtiness || having the [[filth]] spell cast at you, eating filth-crusted items, the effects of a cursed towel. || 1, 4, 15 (3 pts.)
|-
| Disaster || Being affected by [[Famine]]'s reach attacks, having any of the following monster spells cast at you: fire pillar, lightning, geyser, acid rain, blood rain, hail flurry, ice storm, and earthquake. || 1, 4, 15 (3 pts.)
|-
| Seduction || Attacking with—or being hit by—[[seduction]] attacks. || 1, 4, 15 (3 pts.)
|-
| Deep One || Being attacked by a deep one, deeper one, or deepest one. Witnessing a deepest one grow up into [[Father Dagon]] or [[Mother Hydra]]. || 1, 4, 15 (3 pts.)
|-
| Betrayal || Being attacked by a [[pet]] that has become [[Tameness|feral]], a [[traitor]]ous pet, or a [[befouled wraith]]. || 1, 4, 15 (3 pts.)
|-
| Kuo Toa || Being attacked by a [[kuo toa]] or a [[kuo toa whip]]. || 1, 4, 15 (3 pts.)
|-
| Ibite || Being attacked by a [[being of Ib]] or [[priest of Ib]]|| 1, 4, 15 (3 pts.)
|-
| Mind Flayers || Being attacked by [[illithid (monster attribute)|illithid]]s. || 1, 4, 15 (3 pts.)
|-
| Rot || Seeing corpses rot away, [[Spirits|bind]]ing [[Ymir]], seeing [[mold]]s grow on corpses, seeing [[spore zombie]]s revive, being bitten by [[rot caterpillar]]s or being affected by the [[Madness|spores madness]]. || 1, 4, 15 (3 pts.)
|-
| Poison || Hitting with poisoned or dire poison weapons if they trigger the severe effect. Being affected by or attacking with poison monster attacks. || 1, 4, 15 (3 pts.)
|-
| Curse || Having your items cursed by the [[curse items]] spell, being subject to [[mummy curse]]s. || 1, 4, 15 (3 pts.)
|-
| Rot Monk || Being hit by [[rotting monk]]s. || 1, 4, 15 (3 pts.)
|}

==Origins==
Impurity is inspired by the Shinto concept of Kegare, representing how tainted you are by your actions and the things that have happened to you. As you accumulate impurity, certain blood-related effects become more potent, as well as a few other small effects.

{{variant-343}}
[[Category: dNetHack research]]
[[Category: notdNetHack research]]
[[Category: notnotdNetHack research]]

@@ Line 68: / Line 68: @@
 | Mind Flayers || Being attacked by [[illithid (monster attribute)|illithid]]s. || 1, 4, 15 (3 pts.)
 |-
-| Rot || Seeing corpses rot away, [[Spirits|bind]]ing [[Ymir]], seeing [[mold]]s grow on corpses, seeing [[spore zombie]]s revive,<br> being bitten by [[rot caterpillar]]s or being affected by the [[Madness|spores madness]]. || 1, 4, 15 (3 pts.)
+| Rot || Seeing corpses rot away, binding [[Ymir]], seeing [[mold]]s grow on corpses, seeing [[spore zombie]]s revive,<br> being bitten by [[rot caterpillar]]s or being affected by the [[Madness|spores madness]]. || 1, 4, 15 (3 pts.)
 |-
 | Poison || Hitting with poisoned or dire poison weapons if they trigger the severe effect. Being affected by<br> or attacking with poison monster attacks. || 1, 4, 15 (3 pts.)

@@ Line 58: / Line 58: @@
 | Seduction || Attacking with&mdash;or being hit by&mdash;[[seduction]] attacks. || 1, 4, 15 (3 pts.)
 |-
-| Deep One || Being attacked by a deep one, deeper one, or deepest one. <br>Witnessing a deepest one grow up into [[Father Dagon]] or [[Mother Hydra]]. || 1, 4, 15 (3 pts.)
+| Deep One || Being attacked by a [[Deep one (dNetHack)|deep one]], [[Deeper one (dNetHack)|deeper one]], or [[Deepest one (dNetHack)|deepest one]]. <br>Witnessing [[Father Dagon (dNetHack)|Father Dagon]] or [[Mother Hydra (dNetHack)|Mother Hydra]]. || 1, 4, 15 (3 pts.)
 |-
 | Betrayal || Being attacked by a [[pet]] that has become [[Tameness|feral]], a [[traitor]]ous pet, or a [[befouled wraith]]. || 1, 4, 15 (3 pts.)

@@ Line 76: / Line 76: @@
 | Rot Monk || Being hit by [[rotting monk]]s. || 1, 4, 15 (3 pts.)
 |}
 ==Origins==