CoActionDrama is a descriptive, heroic, dice based role-playing system.  Characters have Natures, their innate, “born with” ability levels which describe their natural and innate talents, and Developments, which describe and quantify their skills and abilities as specifically applied to the life that they have led since they were born.  This is to reflect a balance between the Nature/Nurture arguments that follow from studying people as they grow up and develop.

Players control their characters in the usual fashion for role-playing games, and rolls are made to determine the outcome of the interactions between the player/characters and the world often including other player/characters.

It is a feature of CoActionDrama that the system is simple and manageable enough to cope with large numbers of players.  This Author has regularly run 9 people around the table for a five hour session.  Players are expected to use the system to resolve combats, determine the outcome of non-Player-Character (NPC) interactions, (players often control NPCs after a quick private briefing), and even determine the outcome of actions they decide to take themselves.  As the player group this author runs has been 15-20 strong at times, this kind of co-operation is essential.  Players are not in competition with each other, they are co-operating to tell a story, and the outcome of the story can be happy or sad, fortuitous or unfortunate, but the objective is for players to have fun and to find out what happens.

Another feature of the system is the strict interpretation and application of the rules.  This runs counter to most role-playing games where the GM at least is told to “ignore” or “reapply” the rules if things do not seem to be working out.  During the Development of the system we have stopped mid-play (you are not expected to do this!!), and worked out what is wrong with the inception of the rules we have been playing with, before correcting, or noting for future correction, the problem.  It has been surprising how many times a flimsy application of the rules is the problem!  Apply the rules as strictly as possible, it is in the interests of fairness for everyone, and removes the need for constant nit-picking attention by the GM which leads to much more satisfactory player-led role-play. (Hurrahs all round).

Characters have 10 Natures which are divided (very) roughly into mental and physical.  For Humans they are in the range 5-20.  (These may be increased by experience points to a maximum of 25). 

Rolls, on 2d20, are generally made against a Nature and Development added together, plus, if required a modifier in the range 1-10, giving a possible target of -8 to 50. Rolls always succeed on 2, and always fail on 40, even if the target number is higher than 40. 

If a roll 15 or more below the target is made, the success is counted as “good” or “special”.  This means that the task or challenge has been especially easy for the character, and, for example, in combat aiming can achieved without cost (or double dice damage, not both), or in crafting, a higher price can be gained for the item in question.

If a roll of 25 or more below is made, or a roll of 2 is made and it is not the only success possible, the success is “critical”, that is to say, for crafting, a master work is achieved, or for combat, quadruple dice damage can be given, (or aiming and double dice).

Conversely, if a roll or 15 or more above the target is made, the task is not only failed, but failed badly, a “fumble”.  The sword strikes a wall, the bullet hits something unintended and damaging, the work fails, or is undervalued.

If a roll of 25 or more over the target is made, or 40 is rolled, and it is not the only number available for failure, (i.e. the target is 40 or above), then a “critical failure” is made.  The bullet hits someone unintended causing major damage perhaps, the sword hits a friend or that rope holding up the bridge, the work fails at a bad moment, damaging the owner.

The number and type of rolls is determined by the GM, but always remember to apply the rules vigorously, this can save you from embarrassment and confusion when rolls are required.

Players may also make rolls to determine the success or otherwise of an action when they do not know if they would succeed or not, indeed in large groups this behaviour should be encouraged.  Players fill in the gaps in their own knowledge about the world by using the system as strictly as possible.