For decades a satisfactory “single test” mechanic for combat has been something of a Holy Grail for me. Most RPG systems I’ve come across skew heavily towards having crunchier rules for combat than for expertise checks or social situations. Pages of rules are dedicated to things like initiative, movement, attacks, defenses, special maneuvers, injury, and recovery, while mental or social skills usually get a page if they’re lucky.

From my experiences, this is to be expected for two reasons. First, most roleplaying games focus on high adventure: exploring dangerous places, confronting violent villains, and protecting others from harm. Obviously, combat plays a large role in such situations and distilling confrontation to one test diminishes the drama.

Second, there tends to be little extended drama in using mental skills and players that like getting into social situations often rather “roleplay” (to use an emotionally-charged term) through the scenes rather than dice their way to success. Thus, even when the use of mental or social skills is prominent players rarely desire more rules to regulate them.

Still, it seems odd that investigative adventures can chug merrily along with judicious skill rolls only to bog down into an hour-long combat once someone pulls a gun. Shouldn’t this simply be resolved as a single test so the investigation can move forward? Or, if the mystery has been solved and the murderer outed, why does the game need to be dragged out for another half-hour or so if the culprit decides to resist arrest?

In campaigns where combat is to take a minor role it can be tempting to treat combat as just another skill roll. Over the years I’ve periodically tried to do that and was successful in some cases and not so much in others. Here are a few things to keep in mind:

All skills are not created equal. Just because you feel satisfied resolving an encoded puzzle with a single roll doesn’t mean that you’re going to feel that same level of satisfaction distilling a complex diplomatic situation or resolving a fencing duel with single rolls. Some skills simply need a bit more “crunch,” especially if one situation relies on one attribute while another involves several.

Sometimes it’s the mental or social skills that need to get crunchier. If the bulk of your adventures involves gathering and interpreting clues from crime scenes, then maybe all of that shouldn’t be covered by a single Investigate skill. Similarly, in a game of courtly intrigue, you may want the PCs to utilize a half-dozen different types of social interaction roles to make it clearer who specializes in seduction over negotiation or to make some characters better at resisting flattery than accusations.

Most RPGs make several attributes relevant in combat; reducing combat to one skill roll elevates one attribute above others. In most RPG combat rules one attribute is required to attack or defend, one affects damage, and one determines how injury affects a character. By contrast, a Diplomacy roll or Astrophysics roll requires a single attribute. If combat is reduced to a single roll using the attack attribute, then players aren’t going to put much stock in the other two unless they are tied to other important skills.

Some RPGs are weighted towards combat. Reducing combat to a single roll guts the game. I’d wager to say that most iterations of D&D/d20/Pathfinder would be torn asunder if combat was reduced to a single roll, as many feats, special abilities, and spells (not to mention armor class, depending on how you handle the single roll) would no longer be relevant. This may “nerf” some classes in relation to others.

Some RPGs already have time-reducing combat options; these may be enough. In ye olden days I always gave “mook” baddies in my AD&D adventures one hit point per hit die. I’ve seen many RPGs since that have mook/cannon fodder/henchmen rules that speed up combat. These rules are designed to work with the RPG and tend to streamline combats while retaining the flavor of the game. Don’t put in more work than you have to; if these rules do the job then use them!

Can all the variables of combat be adequately distilled into a single roll? So you beat the pistol-armed mook with a combat roll. Did you kill him or knock him unconsious? Does “winning” merely mean he ran away? Was he wounded? Were you wounded? How much did the fight take out of you? While it certainly is possible to resolve combat with a single roll, if you are constantly trying to weigh all of the previous questions whenever combat comes up then maybe it’s a bit more important to your campaign than you’d thought and shouldn’t be handled with a single roll.

If you’ve considered all of these things and still feel that your game can be improved by reducing combats to single dice rolls then here’s a quick and dirty way to do it:

  • Make sure your players are on board. Seriously, there’s nothing worse than going through all this trouble only to find that your players aren’t interested and discarding it five minutes into the session.
  • Use the core skill mechanic.
  • Unless the various physical attributes play essential roles in other parts of the game, reduce them to a single physical attribute. This can be accomplished by averaging physical attributes together or simply by replacing them with one attribute and modifying character generation rules to compensate (e.g. reducing the number of points spent on attribute selection).
  • Eliminate extraneous character options unless you can rework them to influence the single test mechanic.
  • Whenever combat comes up, first determine the desired outcome. While this may involve “defeating the opposition” it could mean other things like “evade the mooks so I can get to the boss” or “hold off the guards long enough so I can dive into the ocean and escape.”
  • Determine what a failure means. If you’re trying to evade the mooks, maybe a failure is getting pinned down behind some crates long enough for the boss to escape. If you’re fleeing the guards, failure could mean that you were captured.
  • Determine what can modify the roll. These include any environmental or situational modifiers.
  • Determine the minimal success by answering the question “You’ve achieved the outcome, but…” The “but” is a complication thrown your way. To continue with the above examples, you evaded the mooks but spent your pistol cartridge, or you held off the guards but you were shot in the leg, leaving a blood trail for nearby sharks.
  • Determine what you need for a solid success. This is an outcome with no complications.
  • Determine what you need for a critical success. A critical success enables you to answer the question “You’ve achieved the outcome and…” You evaded the mooks and managed to run the fleeing boss into a dead end. or you were able to trap the guards in a fishing net, enabling you to continue to search the ship rather than flee.
  • Determine the minimal failure by answering the question “You failed, but…” The “but” opens the door to success with another roll. The mooks have you pinned down but the boss remains behind them yelling into his smartphone for a helicopter extraction. The guards cut off your escape route to the rails but there’s a staircase nearby – maybe you’ll have better luck on a higher deck?
  • Determine the critical failure by answering the question “You failed and.” The “and” is something catastrophic. Not only did you fail to evade the mooks but you’re unconscious and bleeding from a bullet wound. Not only did you fail to escape the guards but you twisted your ankle before being captured.

While these seem like a lot of questions to ask for a single roll, remember that you only have to predetermine the ranges for the various levels of success or failure. With each individual roll, you just need to announce the desired outcome. Everything else can be determined on the fly as necessary.

So what say you? Do you use single combat tests in your campaigns? What issues have arisen? How did the single roll help/hinder your campaign? If you’ve never used it, would you consider it? Have you had any situations where you think a single combat roll might have helped?