Note: ACSX is currently untested and unofficial.
Active Combat System: Experimental is the code name for Feldspar's corollary to the old ACS system. The goal is to maintain the deadliness and GM control of ACS while officiating the crunch (making it feel less arbitrary).
Unlike standard D&D combat, ACS initiative is dependent on the players taking initiative in the form of role-playing decisions. Combat begins when the first character decides to attack. In rare cases, (ambushes for instance) the first turn may depend on one or more character's dexterity save, representing their reflex.
Once the first character takes action, combat follows a free-form order depending on PC and NPC preoccupations. Rather than following a rigid process wherein characters take turns wacking each other, ACS treats combat much like it does any other interaction in DRD4. One of the defining features of ACS is the emphasis on opposed rolls. When one character (the actor) chooses to interact with another character (the reactor), both must make rolls against each other in order to fully represent their skills.
When an acting character decides to attack another character willing and able to fight back, they both enter a state of dueling. Both actor and reactor will make opposed rolls relevant to their equipped weapon. A dueling action will end in a stalemate if their modified rolls are equal. When one roll exceeds another, the action concludes with the character with the higher roll hitting their opponent.
The end of a dueling action does not always end the fight and indeed combat may rage on for several actions.
Hitting an opponent does not necessarily mean injury. Sometimes connecting strikes can be misaligned or glance harmlessly off one's armor. When a character is hit, subtract their combat roll from the opponents combat roll to determine the surplus. If the surplus meets or exceeds the hit character's armor class, they sustain a minor wound. If the surplus meets or exceeds their armor class doubled, they sustain a major wound and if tripled, they sustain a mortal wound.
- Example -- (continued from dueling example)
- Reactor B nets 16 against Actor A's 11
- Reactor B hits with surplus of 5
- Actor A is wearing leather armor and has an armor class of 3
- The surplus 5 exceeds 3 but does not meet 3x2 (6)
- Actor A suffers a minor bludgeoning injury
- GM describes the situation as Reactor B parrying a few swings before walloping Actor A in the arm