Difference between revisions of "Magic contamination"

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{{version|0.19}}
'''Magic contamination''' is a potential side effect of powerful magic, [[divine retribution]] or favour, or the incompetent use of [[magic]].
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'''Magic contamination''' is a dangerous condition caused by miscasts and some magical effects.
  
 
==Overview==
 
==Overview==
Various activities cause harmful magical energies to accumulate in your body. A small amount of magical contamination (a dark grey "Glow" status) is mostly harmless, and will dissipate over time without any further effect. Larger amounts (5+ points) of accumulated magic contamination (a yellow, red, or dark red "Glow" status) will make you start to glow with magical energy.
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Various activities cause harmful magical energies to accumulate in your body. A small amount of magical contamination (a dark or light grey "Contam" status) is mostly harmless, and will dissipate over time without any further effect. Larger amounts of accumulated magic contamination (a yellow, red, or dark red "Contam" status) will make you start to [[glow]] with magical contamination.
  
Glowing is bad for two reasons:
+
The glow from severe contamination makes you easier to hit and reveals you if [[invisible]] (similar to the [[Corona]] spell). Over time you may also suffer damage and [[mutation]]s.
*A glowing target is easier to hit (similar to the effects of the [[Corona]] spell). Similarly, glow can reveal you if you are [[invisible]].
 
*You may suffer damage and mutations from the magical energies your body has absorbed.
 
  
 +
Any amount of contamination can cause [[ugly thing]]s adjacent to you change their colour.
  
==Accumulation==
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==Contamination Levels==
Your magic contamination level can be increased via the following methods. Any behaviour marked with (Z) offends [[Zin]] and will reduce the piety of his worshippers.
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{| class="wikitable"
 +
|-
 +
! Contam<ref>{{source ref|0.19.0|player.cc|4142}}</ref>
 +
! Colour<ref>{{source ref|0.19.0|status.cc|733}}</ref>
 +
! Description<ref>{{source ref|0.19.0|player.cc|4178}}</ref>
 +
|-
 +
| >0
 +
| Light grey
 +
| You are very lightly contaminated with residual magic.
 +
|-
 +
| 3.5
 +
| Dark grey
 +
| You are lightly contaminated with residual magic.
 +
|-
 +
| 5
 +
| Yellow
 +
| You are contaminated with residual magic.
 +
|-
 +
| 15
 +
| Light Red
 +
| You are heavily infused with residual magic.
 +
|-
 +
| 25
 +
| Red
 +
| You are practically glowing with residual magic!
 +
|-
 +
| 40
 +
| Red
 +
| Your entire body has taken on an eerie glow!
 +
|-
 +
| 60
 +
| Red
 +
| You are engulfed in a nimbus of crackling magics!
 +
|}
  
===Haste===
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==Sources==
*Spending time under the influence of [[Haste]] while not [[berserk]].
 
*+1 point for becoming hasted using a Haste spell or [[wand of hasting]].
 
*+1 point for having your already-in-force Haste effect extended by:
 
**Rage extension (Z)
 
**A potion of haste or berserk rage (Z)
 
**Xom sending you berserk.
 
**Invoking Okawaru's Haste power
 
*+2 points for having your Haste extended by:
 
**The Haste spell or a wand of hasting. (Z)
 
  
===Invisibility===
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===[[Invisibility]]===
*Spending time [[invisible]].
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*Evoking turn invisible: 1 to 3<ref>{{source ref|0.19.0|ability.cc|2040}}</ref>
*+1 point for making yourself invisible with a [[wand of invisibility]] or the [[Invisibility]] spell.(Z)
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*While active: 0.03 per turn<ref>{{source ref|0.19.0|timed_effects.cc|718}}</ref> (no dissipation)
  
===Might===
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===[[Haste]]===
*+1 point for extending Might by:
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*Zapped by wand: 0.75 to 1.25<ref>{{source ref|0.19.0|beam.cc|3547}}</ref>
**Quaffing a potion of might (Z)
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*Extending haste: 0.75 to 1.25<ref>{{source ref|0.19.0|player.cc|4767}}</ref>
 +
*While active: 0.03 per turn<ref>{{source ref|0.19.0|timed_effects.cc|721}}</ref> (no dissipation)
  
===Teleport Control===
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Haste like effect from [[berserk]] does not cause contamination.
*+1 point every time you ''successfully'' control a teleportation. This includes semi-controlled [[blink]]s. (Z)
 
*+1 point every time you make a ''fully-controlled'' blink. (Z)
 
  
===Miscasts and Miscast Effects===
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===Spells===
*[[Miscasting]] spells.
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*[[Disjunction]]: 0.75 to 1.25 per cast<ref>{{source ref|0.19.0|spl-transloc.cc|71}}</ref>
*Being struck by the Divinations miscast effect of Sif Muna's wrath.
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*[[Controlled Blink]]: 0.75 to 1.25 per cast<ref>{{source ref|0.19.0|spl-transloc.cc|315}}</ref>
*Unwielding a weapon with the [[distortion]] brand. (Z)
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*[[Irradiate]]: 1 to 1.5 per cast<ref>{{source ref|0.19.0|spl-damage.cc|1508}}</ref>
*The capriciousness of [[Xom]] inflicting a miscast effect on you.
 
*Zot traps (which apply random miscasts).
 
  
===Contaminating Miscast Effects===
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===[[Miscast]]s===
The following miscasts can give you up to 18 contamination:
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*Every miscast: Amount depends on severity etc.<ref>{{source ref|0.19.0|spl-cast.cc|1532}}</ref>
*Severity-3 Enchantments (25% chance)
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*Charms, Hexes or Translocation level 3 miscast (1 in 4 chance): 3d18 / 3 - 1
*Severity-3 Translocations (25% chance)
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*Transmutation level 2 miscast (1 in 5 chance): 3d18 / 3 - 1<ref>{{source ref|0.19.0|spl-miscast.cc|2124}}</ref>
*Severity-2 Transmutations (25% chance)
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*Transmutation level 3 miscast (1 in 3 chance): 3d34 / 3 - 1<ref>{{source ref|0.19.0|spl-miscast.cc|2143}}</ref>
 
 
The following miscasts can give you up to 34 contamination:
 
*Severity-3 Transmutations (25% chance)
 
  
 
===Other===
 
===Other===
*Quaffing a [[potion of resistance]]. (+1) (Z)
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*[[Scroll of blinking]]: 0.75 to 1.25 <ref>{{source ref|0.19.0|spl-transloc.cc|315}}</ref>
*Removing an [[artifact]] that induces magical contamination. This will usually add a minimum of 5 points.
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*Removing an [[artefact]] with *Contam: 7<ref>{{source ref|0.19.0|player-equip.cc|326}}</ref>
*Using an [[amulet of stasis]] to prematurely end a status effect that is prevented by stasis, such as [[Slow]], [[Haste]], or the delay before [[teleport]]ing. This contamination is sometimes harmless (grey), but it has the potential to be hazardous (yellow).
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*[[Mutagenic fog]]: 1.3 to 2.55<ref>{{source ref|0.19.0|cloud.cc|1085}}</ref>
 +
*[[Zot trap]]: 2 to 15<ref>{{source ref|0.19.0|spl-miscast.cc|3276}}</ref> (one of many possible outcomes)
 +
*[[Jiyva]] [[penance]]: 0 to 0.5 * penance<ref>{{source ref|0.19.0|godwrath.cc|1325}}</ref> (one of many possible outcomes)
 +
*Wearing [[Maxwell's Etheric Cage]] doubles all contamination effects<ref>{{source ref|0.19.0|player.cc|4209}}</ref>
  
===Spending Time===
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==Dissipation==
For purposes of the above, "spending time" under the influence of an effect means having that effect in force when the handle_time() function is called (roughly once every 20 turns). When this occurs:
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Magic contamination is dissipated at the rate of 0.025 per turn, 0.012 if holding the [[Orb of Zot]], and not at all if hasted or invisible.<ref>{{source ref|0.19.0|timed_effects.cc|709}}</ref>
*60% chance of +1 contamination if you are invisible.
 
*60% chance of +1 contamination if you are hasted and not berserk.
 
  
==Spell Effects==
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Quaffing a [[potion of cancellation]] removes 1 to 5 points of contamination.<ref>{{source ref|0.19.0|potion.cc|457}}</ref>
Some spells will inflict magical contamination upon the caster:
 
*[[Irradiate]] - 1.5 - 3 points of contamination, meaning the caster can reach Yellow glow status in as few as two successive casts.
 
*[[Disjunction]] - one point of magical contamination per cast.
 
*[[Controlled Blink]] - causes one point of contamination in the same manner as a [[scroll of blink]].
 
  
==Base Contamination for Miscasts==
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While being severely contaminated every 200 to 600 turns<ref>{{source ref|0.19.0|timed_effects.cc|949}}</ref> there is contamination / 12<ref>{{source ref|0.19.0|timed_effects.cc|800}}</ref> chance of a violent release of energies. Standing in a [[sanctuary]] stops this from happening.
To figure the baseline contamination level for a miscast, use the following calculation.
 
  
      A= (spell_level ^ 2) * margin_of_failure
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One likely bad mutation (about 95% chance) is gained that bypasses [[mutation resistance]]. If contamination is higher than 10, there is also a damaging explosion. The damage is 3d(contamination / 2), and doubled for the non-living. Explosion size also increases with the contamination level. After the negative effects contamination is reduced by 1 to 1 + (contamination / 4)<ref>{{source ref|0.19.0|timed_effects.cc|745}}</ref>.
      B= A+250
 
      C= B/500
 
      With C being your final number. Fractional points are rounded randomly.
 
  
==Dissipation==
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==Tips & Tricks==
Dissipation of magic contamination is handled by the handle_time() function. Each time it is called:
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Being in lichform, by way of [[Necromutation]], prevents any contamination-related malmutations; instead, [[rot]] damage is incurred.  
*If you are neither Hasted (whether berserk or not) nor Invisible, you have a 50% chance of harmlessly dissipating one point of magic contamination.
 
*If you have 5 or more points of magic contamination, there is a 50% chance of a violent discharge occurring. The effects of this are as follows:
 
**If you are in a [[Zin|Sanctuary]], there is a ((contamination + 1) × 4)% chance of being told that Zin has prevented a violent discharge of magical energies.
 
**If the previous check failed (either the random roll was too high, or you weren't in a sanctuary to begin with), then there is a ((total contamination + 1) × 4)% chance of some of your contamination discharging violently. When this occurs:
 
***If your contamination total is 10 or higher then there is a 50% chance of a magical explosion erupting from your body.
 
***You receive one mutation. 20% of the time this will be an entirely random mutation; the rest of the time it will be from the list of [[bad mutations]]. If you have mutation resistance from an item, there is a 50% chance that this effect is ignored (down from its inherent 90% resistance chance; be careful!)
 
***A random amount of magic contamination (always at least one point, never more than 25% of your current contamination amount) is removed.
 
 
 
The magical explosions unleashed by violent discharge of magic contamination do damage specified by:
 
dice_def(3, you.magic_contamination × (you.is_undead ? 4 : 2) / 4)
 
For example, if you are not undead, and have 50 points of magical contamination (this is a really, really severe problem...), you will take 3d25 (3-75) points of physical damage (AC applies).
 
 
 
Quaffing a [[potion of cancellation]] will reduce your contamination level by 1d5 points.
 
 
 
One of the aspects of Sif Muna's wrath is reducing the remaining duration of all your enchantments to 1 turn; when this occurs, your magic contamination level is also reduced by 1d5 points.
 
  
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==History==
 +
Prior to [[0.19]], the light grey contamination level didn't exist.
  
 +
Prior to [[0.10]], this effect was simply called [[glow]], a term which ambiguously referred either to magic contamination, or to the relatively harmless glow from [[Sticky Flame]] or [[Corona]].
  
==History==
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==References==
Prior to 0.10, this effect was simply called [[glow]], a term which ambiguously referred either to magic contamination, or to the relatively harmless glow from [[Sticky Flame]] or [[Corona]].
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<references/>
  
 
[[Category:Magic]]
 
[[Category:Magic]]
 
[[Category:Game mechanics]]
 
[[Category:Game mechanics]]
 
[[Category:Status effects]]
 
[[Category:Status effects]]

Latest revision as of 08:14, 15 July 2017

Version 0.19: This article may not be up to date for the latest stable release of Crawl.

Magic contamination is a dangerous condition caused by miscasts and some magical effects.

Overview

Various activities cause harmful magical energies to accumulate in your body. A small amount of magical contamination (a dark or light grey "Contam" status) is mostly harmless, and will dissipate over time without any further effect. Larger amounts of accumulated magic contamination (a yellow, red, or dark red "Contam" status) will make you start to glow with magical contamination.

The glow from severe contamination makes you easier to hit and reveals you if invisible (similar to the Corona spell). Over time you may also suffer damage and mutations.

Any amount of contamination can cause ugly things adjacent to you change their colour.

Contamination Levels

Contam[1] Colour[2] Description[3]
>0 Light grey You are very lightly contaminated with residual magic.
3.5 Dark grey You are lightly contaminated with residual magic.
5 Yellow You are contaminated with residual magic.
15 Light Red You are heavily infused with residual magic.
25 Red You are practically glowing with residual magic!
40 Red Your entire body has taken on an eerie glow!
60 Red You are engulfed in a nimbus of crackling magics!

Sources

Invisibility

  • Evoking turn invisible: 1 to 3[4]
  • While active: 0.03 per turn[5] (no dissipation)

Haste

  • Zapped by wand: 0.75 to 1.25[6]
  • Extending haste: 0.75 to 1.25[7]
  • While active: 0.03 per turn[8] (no dissipation)

Haste like effect from berserk does not cause contamination.

Spells

Miscasts

  • Every miscast: Amount depends on severity etc.[12]
  • Charms, Hexes or Translocation level 3 miscast (1 in 4 chance): 3d18 / 3 - 1
  • Transmutation level 2 miscast (1 in 5 chance): 3d18 / 3 - 1[13]
  • Transmutation level 3 miscast (1 in 3 chance): 3d34 / 3 - 1[14]

Other

Dissipation

Magic contamination is dissipated at the rate of 0.025 per turn, 0.012 if holding the Orb of Zot, and not at all if hasted or invisible.[21]

Quaffing a potion of cancellation removes 1 to 5 points of contamination.[22]

While being severely contaminated every 200 to 600 turns[23] there is contamination / 12[24] chance of a violent release of energies. Standing in a sanctuary stops this from happening.

One likely bad mutation (about 95% chance) is gained that bypasses mutation resistance. If contamination is higher than 10, there is also a damaging explosion. The damage is 3d(contamination / 2), and doubled for the non-living. Explosion size also increases with the contamination level. After the negative effects contamination is reduced by 1 to 1 + (contamination / 4)[25].

Tips & Tricks

Being in lichform, by way of Necromutation, prevents any contamination-related malmutations; instead, rot damage is incurred.

History

Prior to 0.19, the light grey contamination level didn't exist.

Prior to 0.10, this effect was simply called glow, a term which ambiguously referred either to magic contamination, or to the relatively harmless glow from Sticky Flame or Corona.

References