Potion of cancellation

Version 0.29: This article may not be up to date for the latest stable release of Crawl.

Type	Potion
Name	Potion of cancellation
Icon

A potion which ends most magical effects, good or bad, affecting one who drinks it. It also reduces magical contamination.

Quaffing a potion of cancellation immediately ends nearly all status effects you may be enjoying/suffering from. It also removes 1-5 points of magic contamination.

Affected Status Effects

These are also the effects that can be ended from Quicksilver Bolt (including the wand of quicksilver) and Yara's Violent Unravelling. The list of all affected status effects is as follows:

The Bad

• Many action disabling effects:
  • Bad forms
  • Fear
  • Confusion
  • Dimension Anchor (-Tele)
  • Mesmerised
  • Locked Down (-Move)
  • Petrifying
  • Silence (against the source of the aura, like if you cast the spell)
• Many debuffs:
  • Corona
  • Corroded
  • Slow
  • Vertigo
  • Weakness
• Elemental vulnerabilities:
  • Fire vulnerability (rF-)
  • Strip Willpower (Will-)
  • Virulence (rPois-)
  • Scroll of vulnerability (Will 1/2)
• Other effects:
  • Flayed
  • Howl
  • Sap Magic
  • Sentinel's Mark

The Good

• Tele
• Most effects available from potions, excluding berserk:
  • Attraction
  • Ambrosia
  • Brilliance
  • Haste
  • Invisible
  • Might
  • Resistance
  • Agility (formerly from a potion
• Necromancy spells:
  • Animate Dead
  • Death Channel
• Certain other spells:
  • Confusing Touch
  • Disjunction
  • Liquefying (so long as you are the caster)
  • Olgreb's Toxic Radiance (so long as you are the caster)
  • Ozocubu's Armour
  • Portal Projectile
  • Swiftness
  • Wereblood

Unavailable Satus Effects

Either these status effects are exclusive to monsters, or a player wouldn't be able to act while in the status (where a Quicksilver Bolt can end it).

• Antimagic (only a status to monsters)
• Bind Souls, Simulacrum
• Repel Missiles
• Paralysis
• Petrified
• Sleep
• Word of Recall

Resistant Status Effects

Rather than being dispelled outright, these status effects will have their duration set to 1 turn.

• Flight
• All Bad Forms
• All Transmutations not listed above

Unaffected Status Effects

The Bad

• Draining
• No Potions / No Scrolls
• Direct damage:
  • Poison
  • Sticky Flame
• Action cooldowns:
  • -Berserk
  • -DDoor
  • Exhaustion
  • -Hop

The Good

• Berserk
• Death's Door
• Dragon's Call
• Powered By Death
• Polar Vortex
• Quad Damage
• All god-granted status effects

Strategy

Cancellation is incredibly useful for removing a variety of detrimental status effects. Some of the more important statuses include Petrify, Mark from an alarm trap, and bad forms. While it will also remove contamination, using it simply for this purpose is often less useful than for emergency status removal, especially considering that these potions are on the rarer side.

It'll also remove some of the more useful statuses like Haste and Tele, so be careful! This makes enemies with Quicksilver Bolt some of the more threatening monsters in the game.

The following statuses may be ended via other sources:

• Confusion - quaffing a potion of curing
• Teleport - reading another scroll of teleportation
• Slow - negated by haste

History

• Potions of cancellation were added in 0.15, partially taking the role of scrolls of vulnerability.