Bring me glory in combat!
Henzell says...
  1. Wearing a shield gives you a chance to block all damage from some attacks, including arrows, melee, and some spells. Shields prevent off-hand attacks, and until you have enough skill they also slow your melee attacks and make it harder to cast spells. The number of times you can block depends on the size of the shield (see shield[2] for details).
  2. Bucklers can block up to twice per turn, kite shields thrice, and large shields four times. If you have SH without a shield ({amulet of reflection}, mutations, god abilities) you can block once per turn. Attacking faster means your turns go by faster meaning you can block more!
  3. Since 0.28, there are no shield breakpoints and shields do not care about strength. Instead, they scale on dex and scale linearly with shield skill, becoming zero only at 27. Since 0.30, strength helps with spell and attack delay penalties instead of size.
  4. Prior to 0.28, it took 4/15/25 skill to eliminate evasion, melee speed, and casting penalties for bucklers/kite/tower for normal races, 5.6/21/- for kobolds and halflings, 7.2/-/- for spriggans, 2.4/9/15 for nagas, centaurs, and formicids, -/9/15 for trolls and ogres. There may be better uses for your XP than completely eliminating the penalty.
  5. Each enchantment increases SH by 1. Bucklers have 5 SH, -1 EV, max +3; kite shields, 8 SH, -3 EV, max +5; tower shields, 13 SH, -5 EV, max +8. Every level of shield skill increases SH by 1/20 of the base shield value. Dexterity improves your SH bonus from a shield.
  6. You will block a missile if a random number up to 130% of the missile to-hit is less than a random number (on 2 dice) up to 2/3 of your SH; a melee instead uses a random number up to 15 + to-hit / 2. Both to-pass-shield values are inflated by 5 * (previous blocks this turn)^2.
  7. see {shield_formulas}

Information based on master branch and the great LearnDB.
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