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Version 0.30: This article is up to date for the latest stable release of Dungeon Crawl Stone Soup.

For the skill, see Shields (skill). For the item formerly known as just a shield, see kite shield.

“Let who will boast their courage in the field,

I find but little safety from my shield.
Nature's, not honour's, law we must obey:
This made me cast my useless shield away,
And by a prudent flight and cunning save
A life, which valour could not, from the grave.
A better buckler I can soon regain;
But who can get another life again?”
-Archilochos. 7th cent. B.C. trans. William H. Goodwin, 1878.

Shields are a kind of armour worn on one hand, preventing the use of two-handed weapons; they make use of the Shields skill. Unlike other armour, shields increase a character's SH defense, giving you a chance at blocking physical (and some magical) attacks entirely. There are three types of shield, from smallest to largest:

Orbs also occupy your off-hand slot, but provide no shielding, instead granting assorted magical effects from their special egos.

Some magical effects can also increase your SH score.

Shield Penalties

Wearing a shield imposes penalties to attack speed, EV, and spellcasting. While the penalty for wearing a buckler is almost negligible, a tower shield can seriously slow your attacks and make spellcasting unreliable.

EV Penalty

Your shield EV penalty is equal to:[1]

2/5 * encumbrance^2 / (5 + str) * (27 - shield_skill) / 27

Stronger characters are less encumbered by shields, and anyone can eliminate shield penalty by maxing out the Shields skill.

Shield type Encumbrance
Buckler 5
Kite shield 10
Tower shield 15

The EV penalty is subtracted directly from your evasion. Your unrounded EV penalty is also used to calculate the other penalties.

Attack Penalty

The shield penalty, in units of EV, is converted into attack delay, in units of aut.

When you attack with a shield, it'll take 1d(EV_penalty) aut longer.[2] This applies to weapons, missiles, and unarmed attacks. For non-integer EV penalties, it is rounded in a weighted manner before the attack penalty is calculated.

Spell Penalty

The spellcasting penalty is significantly more complicated. Shields add to "SpellFailure", not to be confused with your actual % chance of failure:

spell failure = 19 * ev_penalty

For reference, 12 SpellFailure = 1 level in every spell school (excluding Spellcasting). 15 SpellFailure = 1 level in every school, including Spellcasting.

This number is then modified by various functions described in the spell success page.


Bucklers, kite shields, and tower shields can spawn with the following egos[3]:

Shields of cold and fire resistance can also occasionally be found in ice caves and volcanoes, respectively.

Every orb has its own ego; see the orb page for more details.


As long as your SH is above 0, you can block melee and ranged "projectile" attacks.

All melee attacks can be blocked (except for successful stabs), but many types of ranged attacks are unblockable:

Orb of Destruction is the only spell that ignores EV, but can be blocked.

Some examples of ranged attacks that can be blocked:

If the attacker's pierce value is less than the defender's blocking value (see below for details), the attack does no damage. Shield blocking is done before rolling your evasion or your AC, but if you have already blocked some attacks in that turn, your blocking ability will be decreased greatly. Your ability to block missiles doesn't benefit from repulsion or EV.

SH calculation

If you are wielding a physical shield, its SH is determined as follows:[4]

All other sources of SH (Qazlal shield, amulet of reflection...) are flat bonuses, and are added on top of the physical shield bonus. The final value is rounded to the nearest integer and displayed as the player's SH value.

If you are paralysed, petrified, or if dexterity is 0, then SH is set to 0 regardless of any other factors.

Chance to block

The game compares the attacker's "pierce value" to the defender's "block value".

The attacker's pierce value is dependent on their to-hit (accuracy) and the type of attack:

  • Melee attack: 1d(15 + to_hit/2 + 5×past_blocks^2)
  • Ranged attack: 1d(1.3×to hit + 5×past_blocks^2)

The defender's blocking value is equal to:

  • All attacks: 2d(2×SH)/6 - 1.3
  • Divide by 3 against melee attacks from invisible opponents.

If the blocking value is greater or equal than the attacker's pierce value, the attack is blocked.


  • Prior to 0.30, species size impacted shield encumbrance and SH score. Larger species were less encumbered by shields, but received slightly less SH from kite shields. Smaller species were the opposite, more SH from bucklers/kite shields, but more encumbered by them.
  • In 0.28, magical orbs were added as a new category of off-hand equipment.
  • Prior to 0.28, shields had a different penalty formula, EV_penalty - skill / (5 + size_factor) (buckler = 0.8 EV, kite shield = 3, tower shield = 5). Using shields at 0 skill was more encumbering, but certain skill thresholds (regular size species: 4 skill for buckler, 15 for kite shield, 25 for tower shield) negated penalties entirely. They also had a to-hit penalty. In addition, the two larger shields used strength (along with dexterity) to determine bonus SH.
  • Prior to 0.27, shields had a smaller penalty to attack delay (previously: smaller of {1d(20 * EV)/20, 1d(20 * EV)/20}, then rounded in weighted manner, instead of 1d(EV)).
  • Prior to 0.25, kite shields were known as just "shields" and tower shields were called "large shields".
  • Prior to 0.17, unarmed attacks had a speed penalty when attacking with a shield equipped.
  • Prior to 0.16, the amount of skill required to negate penalties for wearing a shield was more complex.


  1. (0.30.0)
  2. (0.30.0)
  3. (0.29.1)
  4. (0.30.0)
    These values are divided by 200 by later functions.
  5. (0.30.0)
    Divided by 2 by a later function.
Body Armour Leather armourRing mailScale mailChain mailPlate armourCrystal plate armour

RobeAnimal skinTroll leather armourSteam dragon scalesAcid dragon scales
Swamp dragon scalesQuicksilver dragon scalesFire dragon scalesIce dragon scales
Pearl dragon scalesShadow dragon scalesStorm dragon scalesGold dragon scales

Miscellaneous HatHelmetCloakScarfGlovesBootsBarding
Shields BucklerKite shieldTower shieldOrb