Line of sight

Version 0.30: This article may not be up to date for the latest stable release of Crawl.

Line of sight (often abbreviated to LOS) refers to the portion of the Dungeon that you can see. The default LOS used by most species is out to 7 spaces, or a 15x15 square.

Line of sight is similar to, but distinct from, "line of effect" (i.e. the area of the Dungeon you may interact with). Most of the time, they are interchangeable, but some situations may result in places you can see but not affect (such as tiles behind transparent walls) or can affect but cannot see (such as Fireball's explosions hitting foes around corners).

The following picture shows tiles within the default field of view with their grid distance.

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Altering LOS

There are some ways to change your line of sight:

• A scarf of shadows reduces LOS by 1.
• The Robe of Night reduces LOS by 25%, rounded down.
• Kobolds start with rank 3 of Nightstalker, reducing LOS by 3 tiles to 4 spaces (9x9 square).
• Barachim have an innate mutation that increases their default LOS by 1, to a total of 8 spaces (17x17 square).

Strategy

If you can't see them, they can't see you. With very few exceptions, enemies that can't see you can't attack you.

There are several ways to break your line of sight with an enemy:

• Teleporting/blinking out of range
• Closing doors
• Turning a corner
• Reading a scroll of fog
• Going up/down stairs or shafts
• Imprisoning them, or yourself
• Running away faster than they can chase you.

Because LOS is square, exploring in a diagonal direction will reveal more tiles than exploring in a cardinal one (all else equal). If you want to find an Abyss exit or uncover the most tiles for Meteoran regeneration, move diagonally.

History

• Prior to 0.17, line of sight was circular, with a radius of about 8. You could see slightly less tiles overall, and saw much less in diagonal directions. Characters could reach their target in 5 squares (instead of 8) at certain angles.

Ranges were also circular; up to 2 tiles of range were lost when shooting diagonally. For example, Bolt of Fire could shoot 7 tiles in a cardinal direction, 5 in a diagonal one, and 6 in-between. Base ranges across the board were 1 higher than they are in current versions.

• Prior to 0.7, abilities and spells had rectangular ranges instead of circular ranges.

Changing LOS

• In 0.26, the LOS-reducing shadows ego was added, the Darkness spell was removed, and Nightstalker was changed from a potential Demonspawn mutation to a Kobold innate ability.
• In 0.20, Barachim and their unique +LOS mutation were added.
• Prior to 0.19, the Shadow card existed and could be used to further reduce the player's LOS.
• Prior to 0.18, the lantern of shadows existed and could be used to further reduce the player's LOS.