Armour

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Version 0.32: This article is up to date for the latest stable release of Dungeon Crawl Stone Soup.

For the skill, see Armour (skill).

Nought can Deform the Human race
Like to the Armours iron brace"

-William Blake, "Auguries of Innocence", 99-100. 1803.

Armour encompasses all equipment worn to protect against attacks. Armour increases your armour class (AC), which defends against melee, ranged, and most magical attacks. It can also have egos, which provide further benefit.

However, body armour is encumbering. Wearing heavier body armour will lower your EV and stealth, increase chance of spell failure, and slow down Ranged Weapons. These penalties are reduced, but not eliminated, by strength and Armour skill. Only body armour and shields have encumbrance penalties; all other armour can be worn at no cost.

Shields increase SH instead of AC, but are usually considered a piece of "armour" as well.

Armour Locations

There are six armour locations in Crawl, also known as armour slots. Some species have restrictions on the kinds of armour they can wear, while many Transmutations will render pieces unusable.

  • Body armour is worn on a character's torso, and is the primary source of AC. Its AC bonus is penalized by the Deformed mutation. Heavier body armour imposes greater penalties.
  • Gloves are worn on the hands, and are unusable with rank 3 of the Claws mutation.
  • Boots are worn on the feet, and are unusable with rank 3 of either the Talons or Hooves mutations.
    • In place of boots, Armataurs and Nagas can wear bardings on the rear portions of their bodies. They provide more AC and higher potential enchantment, but slightly reduce your EV.
  • Helmets and hats are worn on the head. The Beak, Antennae, and Horns mutations all restrict the player's headgear options.
  • Cloaks and scarves are worn around the shoulders, which are unusable with demonspawn's Weakening Stinger.
  • Shields and orbs are held on character's arm. They prevent the use of two-handed weapons. Shields provide SH, but impede spellcasting and EV without sufficient skill.

All armour types, including shields, take 5 turns to remove and 5 turns to put on. If you swap from one piece of armour to another, it takes 10 turns total. If you are hurt when (un)equpping armour, the game will ask if you want to abort the action.

Encumbrance Rating

Most body armour has an encumbrance rating proportional to its AC. Robes and leather armour, being lightweight, have little or no EV penalty; at the other end of the spectrum you can find plate armour and crystal plate armour, which are cumbersome but incredibly protective.

A higher encumbrance rating:

Increasing your Armour skill decreases the effect of the encumbrance rating (-2.2% per level, or -60% at Armour 27) and boosts the total AC granted by those pieces. High strength will also help. Stealth is always penalized the same. See the encumbrance rating page for more details.

Shields have an encumbrance rating, but it works differently from body armour. See Shields for more details.

Only body armour and shields have an encumbrance rating. Bardings have an EV penalty, but this is unrelated to ER.

Calculating AC Value

Base AC & Armour skill

Your total "base AC" is equal to the sum of the base AC values from every worn armour. This excludes any armour enchantments you may have.

Then, Armour skill provides a bonus to AC, using your base AC:[1]

  (base AC) * (1 + Armour_skill / 22)

This is roughly equivalent to +4.5% base AC per level of Armour skill. AC is calculated to 2 decimal places, and most displays show this value rounded down. Item descriptions will, however, show your AC rounded to 1 decimal place, together with the change in AC from equipping or removing that item.

Body Armour Penalties

There are two penalties that lower your body armour's base AC. These are calculated after the bonus from Armour skill. These do not impact enchantment or other armour types.

  • If you have the Deformed or the Pseudopods mutation, you lose <body armour base AC> * 0.5 AC. These mutations do not stack with each other.
  • If you are in Blade Form and under 19 Shapeshifting skill, you lose <body armour base AC> * (19 - Shapeshifting) / 9 AC. This cannot be greater than your body armour base AC.

If both penalties apply, they stack multiplicatively, for a total loss of (1 - <body armour base AC>) * 0.5 * <Blade Hands Modifier> AC.

Bonuses

All other sources of AC are flat, additive bonuses to your AC score, which are not impacted by armour or Armour skill:[2]

Tables of Armours

Body Armour

Armour Base AC Encumbrance rating Wearable
Robe 2 0 All
Leather armour 3 4 Small–Medium
Ring mail 5 7 Small–Medium
Scale mail 6 10 Small–Medium
Chain mail 8 14 Small–Medium
Plate armour 10 18 Small–Medium
Crystal plate armour 14 23 Small–Medium
Animal skin 2 0 All
Troll leather armour 3 4 All
Steam dragon scales 5 0 All
Acid dragon scales 6 5 All
Swamp dragon scales 7 7 All
Quicksilver dragon scales 9 7 All
Fire dragon scales 8 11 All
Ice dragon scales 9 11 All
Pearl dragon scales 10 11 All
Storm dragon scales 10 15 All
Shadow dragon scales 11 15 All
Golden dragon scales 12 23 All

Shields

Shield SH Encumbrance Wearable
Buckler 3 5 Little–Medium
Kite shield 8 10 Small–Big
Orb 0 0 All
Tower shield 13 15 Medium–Giant

Headgear

Headgear AC Encumbrance rating Wearable
Helmet 1 0 Small–Medium
Hat 0 0 All

Miscellaneous

Armour AC Encumbrance rating Wearable
Boots 1 0 Small–Medium
Cloak 1 0 All
Scarf 0 0 All
Gloves 1 0 Small–Medium
Barding 4 -6 Naga/Armataur

Egos

Enchanted armour may have an ego, which gives it additional properties.

Restrictions and Mutations

  • Beaks, horns, and antennae are incompatible with helmets. Hats are allowed.
    • Horns 3 and Antennae 3 disallow all headgear, however.
  • Hooves 3 and talons 3 are incompatible with boots.
  • Claws 3 and Blade Hands are incompatible with gloves.
    • Blade Hands is in addition incompatible with all types of shields and weapons.
  • Weakening stinger is incompatible with cloaks.
  • Wisp Form is incompatible with all armour and jewellery.
  • Bat Form and Pig Form are incompatible with all armour and rings (you can only wear amulets).
  • Fungus Form, Spider Form, Ice Form, Storm Form, and Dragon Form are incompatible with all armour (you can only wear jewellery).
  • Tree Form is incompatible with all armour except shields.
  • Statue Form is incompatible with all armour except headgear, shields, and cloaks.

History

  • Prior to 0.32, AC was always rounded down to an integer, meaning AC would increase at specific breakpoints in Armour skill, rather than increasing smoothly.
  • Prior to 0.29, body armour encumbrance did not slow down Ranged Weapons.
  • Prior to 0.28, armour and shields would penalize your to-hit.
  • Prior to 0.27, GDR was determined based on your body armour, not from total AC.
  • Prior to 0.17, heavy armour slowed throwing and unarmed combat attacks.
  • Prior to 0.16, light armour had no small spellcasting success penalty.
  • Prior to 0.15, armour took AC + 1 turns to unequip or equip (instead of a flat 5 turns).
  • Prior to 0.14, racial armour types existed. Elven armour impeded spellcasting less, dwarven armour had more AC but impeded casting more, and orcish armour was better for Hill Orcs only.
  • In 0.13, the evasion penalty system was changed. "Base Evasion Penalty" (BEVP) was changed into encumbrance rating, and rescaled for all armours (see dev wiki).
  • Prior to 0.11, you could only train Armour while wearing equipment with an EV penalty of at least -1.
  • Prior to 0.6, body armour was divided into "Light Armour" and "Heavy Armour". The former would allow you to train Dodging, while the latter trained Armour.

Changes to armour types

  • In 0.30, chain mail had encumbrance reduced (from 15 -> 14).
  • In 0.29, shadow dragon scales had its AC increased (10 -> 11).
  • Orbs were introduced in 0.28.
  • Prior to 0.26, bardings were split into naga bardings and centaur bardings.
  • Scarves were added in 0.20.
  • Prior to 0.19, dragon scales were named dragon armours. Also, trolls/dragons only dropped hides; you had to use a scroll of enchant armour on the hide to get the armour.
  • In 0.16, scale mail had encumbrance reduced (11 -> 10).
  • In 0.14, gold dragon armour, crystal plate armour, and plate armour have had their encumbrance ratings reduced (27 -> 25, 24 -> 23, and 19 -> 18 respectively). Mottled dragon armour increased ER from 4 to 5.
  • In 0.13, splint mail was removed.

References

  1. player.cc:5691 (0.28.0)
  2. player.cc:5914 (0.28.0)
Skills
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