Invisible

Version 0.26: This article may not be up to date for the latest stable release of Crawl.

Invisible is a status effect which renders the target unseen except through see invisible. It functions differently depending on whether it affects a player or a monster.

Player Version

An invisible player gets the following bonuses and penalties, assuming your victim cannot see or sense invisible:

• Anyone attacking you in melee incurs a 35% reduction to their to-hit number.
• Any of your melee victims who have shields have their blocking roll divided by three.
• You occasionally make low-tier stabbing attacks, and sleeping or unaware monsters suffer a large penalty to detecting you through your stealth.
• Enemy ranged attacks have their to-hit number halved, and may target the wrong tile entirely.
• Monsters are less likely to use certain spells or abilities against you.
• There is a chance opponents who can't see invisible will break off their attack and resume wandering.
• You have a 60% chance of gaining a point of magic contamination when handle_time() is called.
• You can only dissipate magic contamination via "violent discharge" or the wrath of Sif Muna.

Sometimes monsters can guess the position of an invisible player:

• Seeking monsters will randomly target a nearby tile when the player is within two tiles.
• Monsters have a 33% chance to guess the player's tile if the player is right next to them.
• Intelligent monsters have an extra 8% change to guess the player's position.
• Additionally, Ashenzari penance improves the chance of guessing by 50%.

Invisibility has no effect if the player is in water or glowing.

Sources

You can become invisible by:

• quaffing a potion of invisibility.
• casting the level 6 Hexes spell Invisibility on yourself.
• using the Evoke Invisibility ability granted by a scarf of invisibility or certain artefacts (attempting to use this ability, succeed or fail, will drain you).
• zapping yourself with a wand of random effects (5.5% chance).
• Dithmenos' Shadow Form turns you into a shadow, granting intrinsic invisibility.

Regardless of source, player invisibility lasts for 15 + 1d(spell power) turns (max: 100 turns).

Strategy

Stealthy stabber characters can benefit tremendously from being invisible; it greatly enhances both your ability to go undetected around susceptible enemies and your damage output in melee with them thanks to the stabbing opportunities it provides. Even characters that do not specialize in stabbing can benefit from invisibility -- enemies that can't see you have a hard time hitting or blocking you in combat, and will have difficulty tracking you should you need to make an escape.

Despite the benefits, there are still significant downsides to invisibility:

• The list of monsters capable of seeing invisible is unfortunately rather large (see Category:See invisible), making the status effect completely useless against them.
• Potions are reliable, but are rare and come in limited quantity.
• A wand of random effects might turn you invisible, or it might blast you with one of several harmful effects. Additionally, using it against hostile creatures might turn them invisible instead of hurting them.
• Having an item with evocable invisibility is the easiest way to gain unlimited access early on, but finding such equipment is by no means guaranteed. Additionally, over-reliance on this ability (especially without significant training in Evocations to improve your chance of success) will leave you with greatly reduced HP.
• The Invisibility spell is both reliable and reusable, but gaining the skill necessary to cast a level 6 spell can be prohibitive for many builds. Even once you can comfortably cast the spell, overuse rapidly generates magic contamination, eventually negating your invisibility and putting you at risk of bad mutations and irresistible damage.
• Shadow Form requires significant Invocations training to be reliable, carries a significant MP and piety cost, drains you when activated, further drains you when you take damage, and reduces your damage output and spellpower.

As an alternative, consider learning the Dazzling Flash spell. This level 3 spell blinds opponents, duplicating many of the advantages of invisibility without some of its limitations and affecting many opponents that possess see invisible.

Monster Version

Invisible monsters are very dangerous to a player who cannot see invisible. If you cannot see invisible, then in melee with invisible monsters:

• Your block rolls are divided by three.
• You suffer a -10 penalty to your EV against their melee attacks
• You suffer a -6 penalty to your melee to-hit number against invisible monsters.

On top of that, invisible monsters cannot be seen either within your line of sight or on the map, and if you actually manage to guess which tile they're in and attack them, you receive significantly less information than normal (the monster is referred to as "something" rather than by its actual name).

Sources

Permanently invisible

These monsters are permanently, inherently invisible:

• x Unseen horror
• y Ghost moth
• W Shadow wraith
• 2 Lorocyproca

Casters of invisibility

Some spellcasting monsters can make themselves invisible:

• o Orc wizard (66% chance)
• I Sky beast (by inherent ability, not a spell)
• p Shadow (by inherent ability, not a spell)
• O Ogre mage (33% chance)
• e Deep elf knight (50% chance)
• V Vampire
• V Vampire knight
• V Vampire mage
• g Boggart
• p Necromancer
• p Wizard (33% chance)
• q Draconian knight
• L Lich (40% chance)
• L Ancient lich (40% chance)
• @ Sigmund
• o Blork the orc
• @ Psyche
• x Erica
• f Maurice
• O Erolcha (33% chance)
• @ Kirke
• m Ilsuiw
• L Boris
• i The Enchantress
• & Pandemonium lord (7.5% chance)

This effect has a finite duration, but the monster can always recast it after it has run out.

Potion users

Monsters who know how to use potions may use potions of invisibility to make themselves invisible. This effect has a finite duration, but the monster may be able to reapply the effect by quaffing another potion (if it has one).

Detecting invisible monsters

See invisible

If you have the see invisible intrinsic, invisible monsters gain no benefits against you. You can acquire this in the following ways:

• Having the Acute Vision mutation. Spriggans, vampires, nagas, felids, and palentongas all have this mutation naturally.
• Having rank 3 of the Antennae mutation. Formicids start with this, and demonspawn may develop it as they grow.
• Wearing a ring, headgear, or artefact with the see invisible ego
• Having rank 3 of Jiyva's Eyeballs mutation.

Backlighting

Under some circumstances, a target may become backlit (also known as glowing). This renders its invisibility ineffective, and actually makes it easier to hit than normal. Backlighting occurs whenever:

• An invisible target is affected by the Corona spell (must overcome willpower).
• An invisible, corporeal target (i.e. one that is not insubstantial) is covered with Sticky Flames, unless it's standing in water (which immediately extinguishes the flames).
• An invisible creature enters a halo.
• The player suffers from significant amounts of magical contamination (yellow or worse).

Invisible monsters revealed as a disturbance

All invisible monsters will occasionally leave disturbances while invisible, represented by a white humanoid outline if playing in tiles or by the { glyph if playing in console. If you attack a square and the monster does not move from that square, the monster will be revealed as a disturbance until it moves (the only invisible monsters likely to shift position without you moving first are unseen horrors).

All corporeal invisible monsters create disturbances when passing through an opaque cloud (e.g. fog, steam), revealing their position (but not any further information). Do note that this only applies to monsters -- invisible players are not revealed in clouds. Anything the player can do to create clouds when an invisible creature is near will aid him in determining that creature's location:

• Reading a scroll of fog, evoking the cloak of the Thief, or bleeding smoke (granted to followers of Dithmenos).
• Using Fire Magic in and over water, creating steam clouds.
• Using Ice Magic in and over lava, creating steam clouds.
• Invoking Wu Jian's Heavenly Storm ability.

Additionally, any invisible creature standing or swimming (e.g. not flying) in liquid (shallow water, deep water, and lava) is always visible as a disturbance.

History

• Prior to 0.26, the invisibility ego did not drain its user when used.
• Prior to 0.22, the submerging mechanic existed. Certain monsters had an ability to render themselves effectively invisible by hiding in deep water, lava, or even under the floor.
• Prior to 0.20, invisibility increased the player's hunger rate by 5.
• Prior to 0.18, invisibility reduced the combat accuracy by 5 for the player and monsters if they couldn't see invisible themselves.
• Prior to 0.16, the sense invisible intrinsic existed, which was an upgrade to see invisible.
• Prior to 0.13, invisible monsters were immune to the effects of Olgreb's Toxic Radiance.