Mephitic Cloud

Version 0.28: This article may not be up to date for the latest stable release of Crawl.

Mephitic Cloud
Level	3
School1	Air
School2	Alchemy
School3	Conjuration
Source(s)	Book of the Senses Book of Vapours
Casting noise	3
Spell noise	15
Power Cap	100
Range	4
Flags	Area, Cloud, Dir or target, Needs tracer

Conjures up a short-lived cloud of noxious fumes, which may cause confusion in any creature not resistant to poison. Tougher, more experienced creatures are less likely to be affected. “Seit mehreren Jahren schon hatte die indische Cholera eine verstärkte Neigung zur Ausbreitung und Wanderung an den Tag gelegt. Erzeugt aus den warmen Moraesten des Ganges-Deltas, aufgestiegen mit dem mephitischen Odem jener üppig-untauglichen, von Menschen gemiedenen Urwelt- und Inselwildnis, in deren Bambusdickichten der Tiger kauert, hatte die Seuche in ganz Hindustan andauernd und ungewöhnlich heftig gewütet, hatte östlich nach China, westlich nach Afghanistan und Persien übergegriffen und, den Hauptstraßen des Karawanenverkehrs folgend, ihre Schrecken bis Astrachan, ja selbst bis Moskau getragen.” -Thomas Mann, _Der Tod in Venedig_, 1911.

Mephitic Cloud is a Level 3 Conjurations/Poison/Air Magic spell that creates up to a 3x3 cloud of noxious fumes which will linger for several turns. It does not affect unbreathing creatures (undead, nonliving, and plants), nor those that are poison resistant.

Any other creature caught in it will have a (21 - hit dice) in 21 chance per turn to become confused, unless the creature is immune to poison or clouds. Monsters with 22 hit dice or more have a flat 2% chance to be affected.

The clouds stay a duration of 1d (Spell power / 50) turns.

Mephitic Cloud makes as much noise as Fireball.

Strategy

This spell is found in multiple spell books, including several starter spellbooks. Despite how it can be blocked by two different resistances, it is very useful, even with minimal skill in the relevant magic schools. It is highly effective against most of the most dangerous monsters in the early to mid game, such as centaurs, spellcasting orcs, and yaks.

The confusion effect essentially disables creatures and allows you/your minions/your spells to kill them much more easily. The longer they spend in the cloud, the longer the victims will be confused. Alas, it will not affect undead or other poison-resistant enemies, but those can sometimes be distracted by attacks by their confused neighbors.

If you are poison-resistant, have the clarity intrinsic, or are worshipping Qazlal, you can use it anywhere without fear of affecting yourself. If surrounded, you can even target yourself.

Even if you're not poison resistant, Mephitic Cloud can be used against an adjacent enemy in most cases (aim at the *):

.........  .........
...###...  ....###..
...#*#...  ....#*#..
...##Y...  ....Y##..
....@....  ....@....
.........  .........

By targeting diagonally beyond the yak, you can catch it in the cloud radius without catching yourself.

Also note that risking self-confusion is sometimes worth it - you can always drink a potion of curing (which you might have been wanting to do anyway), and most enemies can't.

Since Mephitic Cloud can be targeted at an empty square, this increases its effective range by one, allowing you to catch an enemy just beyond its normal range. When facing distant enemies with dangerous ranged attacks (such as centaurs), a good strategy is to drop a cloud between you and them, then back away until they blunder into it.

Tips & Tricks

• If you come across Ignite Poison, you can use Mephitic Cloud even against monsters that resist it. Surround your foes with noxious fumes, then light them on fire!

History

• Prior to 0.28, noxious fumes would deal minor (0-2) poison-based damage while in them.
• Prior to 0.10, Mephitic Cloud guaranteed a 3x3 cloud.