One difference between AD&D and later editions is that players must declare their actions before rolling for initiative; though not explicitly listed as a step on page 61 of the DMG, it is inferred by the rules.
At the beginning of each combat round, initiative is normally determined by rolling 1d6 for each side. The side with the higher result possesses initiative for that round. Remember that each combat round consists of 10 segments. If party A rolls a 4 and party B rolls a 2, party A possesses initiative for that round and will get to act first. Which segment each party gets to act is determined by the opposite party’s initiative roll; for example, party A acts on segment 2, and party B acts on segment 4.
Dexterity Bonuses and Penalties
Individuals’ Dexterity attacking adjustment for missile weapons will modify the initiative on an individual basis. Therefore, it is possible that an individual on a side that lost initiative will still be able to perform a missile attack before the other side. These bonuses do not apply to individuals carrying more than light gear (see PHB page 102); penalties always apply.
Multiple Attack Routines
When an individual is permitted to use an attack routine multiple times during a round, special initiative rules apply.
- If the attack routine may be used twice:
- If possessed by one side, those individuals attack first and last
- If possessed by both, use initiative rolls to determine who strikes first and third and second and last.
- If an individual can only use an attack routine once per round, their attack will occur in between those with two, with order being determined by initiative rolls when necessary.
- If three times:
- The other party rolls for initiative to see if it or the multi-routine individuals strike first the midpoint of the round.
Note that a target must survive damage from previous attacks for one to follow their attack routine.
When opponents are begin a round over 1″ away (10′ indoors, 10 yards outdoors) from each other, melee is not possible. One side may either spend the round closing the distance or charge. Encumbered creatures are not allowed to charge.
Those receive movement bonuses:
- Bipeds: +33 1/3%
- Quadruped: +50%
Dexterity bonuses to armor class do not apply when charging. Those with no Dexterity AC bonus suffer a +1 to AC. There is no penalty for those with an AC of 10.
Initiative is not checked at the end of the charge. The opponent with the longer weapon attacks first. Charging creatures gain +2 to-hit if they survive.
Casting times determine when spells will be completed. If there is a tie, initiative breaks the tie.
If a spell caster is being attacked by a melee weapon and the attacker has won initiative, the weapon strike will always occur first. If initiative is tied, compare the casting time with the melee weapon’s speed factor. If the attacker loses initiative, subtract the attacker’s initiative from the weapon’s speed factor; treat negative numbers as positive, and compare the result.
If the spell caster is being attacked by a missile weapon or natural weapons without a speed factor and the attacker wins initiative, the attack will always occur first. If the attacker loses initiative or initiative is tied, the attack will occur on the segment indicated by the caster’s initiative die. Compare it to the spell’s casting time.
If the attacker has multiple attack routines, only the first attack can disrupt the spell (unless the spell’s casting time is a full round).
The caster cannot use their Dexterity bonus to avoid being hit; otherwise, the spell is disrupted. Any successful attack interrupts the spell.
Weapon Speed Factor
When initiative is tied and both are using melee weapons with speed factors, weapon speed factors determine order. The melee weapon with the lower speed factor strikes first. Under the above circumstances, one may be entitled to multiple attacks. If the difference between speed factors is 5-9, the one with the lower speed factor is entitled to 2 attacks before the opponent can attack. If the difference is 10 or greater, the one with the lower speed factor is entitled to 2 attack before the opponent can attack, and they are entitled to 1 more attack at the same time their opponent is finally able to attack.
Speed factor considerations do not apply when closing or charging to melee.