Roll to Hit
Describes the roll necessary to hit an opponent with a weapon, touch an opponent or — sometimes — to hit with a magically propelled force such as Melf's arrow or spiritual hammer. The success of a given roll is determined by THAC0, in which the chance to hit is determined by the attacker's experience level and the opponent's armour class (AC).
Note that rolls of 1, 2 or 20 are important as they invoke critical hit & fumble rules.
Penalties and bonuses to hit modifies the die roll, or rather the number needed to hit. Below is a list of the most common modifiers (with expectations that this list will eventually be complete):
- Cover: defenses offered by fortifications, vegetation or terrain can offer varying attack modifiers depending on the position of the combatant.
- Groggy: applies when the character initially awakes from sleep; -2 to hit.
- Illumination: the amount of illumination and comparable darkness affects the chance of combatants to hit, particularly with missile weapons.
- Invisibility: because of the nature of invisibility in the game, there is normally no chance of hitting an invisible creature if it is not detected. Character with heightened senses may enable a character to hear the creature breathing, however, so that attacks in such cases may be made at -4 to hit, with the skilled character being able to positively identify the invisible defender's hex. Characters that shimmer translucently are attacked at -2 to hit. [unlike AD&D specifies, no % bonus is given for leveled persons to identify invisibility according to their experience.]
- Magic: many different spells offer adjustments to hit and damage that affect both attackers and defenders; adjustments are noted under their spell descriptions. Noted defensive spells include protection from malevolence, barkskin, stoneskin, armour and phantom armour. Attack spells that include a roll to hit are Melf's arrow, spiritual hammer, chromatic orb, magic stone and shocking grasp. These spells ignore armour, so that attacks are made against AC 10. Spells that adjust the abilities of the character or object (strength, flame blade, shillelagh) roll to hit normally.
- Missile Ranges: when attacking opponents with missile weapons at a range of 2 hexes, the modifier is +1 for the attacker. Attacks at medium range are done at -2 and at long range at -5.
- Paladin Class: paladins are continuously protected by protection from malevolence, subtracting 2 from all attacks made against them.
- Rear & Flank Attacks: rear attacks receive a +2 bonus to attack; thieves and assassins will receive +4 against the rear, when the opponent is surprised. Flank attacks receive a +1 bonus to attack.
- Strength Ability: subtracts or adds to the attack die when using hand-to-hand weapons, depending on the attacker's strength.