Line of sight

Version 0.25: 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.

There are some ways to change your line of sight:

• The spell Darkness reduces LOS by 25%. The same effect is also provided by the Robe of Night.
• The demonspawn-exclusive nightstalker mutation reduces LOS by 1, 2, or 3 tiles depending on its rank.
• Barachim have an innate mutation that increases their default LOS by 1, to a total of 8 spaces (17x17 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 firing a bow into a cloud of smoke).

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

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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.

History

• In 0.26, Kobolds will start with Nightstalker 3; Demonspawn will no longer have Nightstalker among their possible mutations. Also, scarves of shadows will be added, and the Darkness spell will be removed.
• 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.
• Prior to 0.17, line of sight was circular with a radius of about 8.
• In 0.7, the developers made an undocumented change to the LOS. Ranges became circular, so every spell and ability with a set range got about two squares lopped off the diagonals. Stealthy characters could reach their target in 5 squares (instead of 8) at certain angles.