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Checks Versus Attack Rolls: Every Aspiring RPG Designer (and Some Veterans) Should Read This

One of the great innovations of roleplaying game design came in 1977 when Steve Perrin and his Runequest design friends realized the advantage of using the same mechanic for attacks and skill checks. One core mechanic replaced the jumble of different mechanics that D&D used to determine if an attack landed, if a lock opened, if a secret door was spotted, and so on. Core mechanics brought a simplicity and consistency that makes RPGs easier to learn and play. Now even D&D follows Runequest’s example. Attacks work almost exactly like ability checks and saving throws.

But do roleplaying games play better when attack rolls work differently from other ability or skill checks? After all, D&D characters tend to make far more attack rolls than ability checks. And unlike most attack rolls, single ability checks open doors—literally and figuratively, and steer the course of an adventure.

table with battlemap and ship at winter fantasy 2025Some newer games break the pattern of making checks and attacks the same. In Draw Steel attack rolls and ability checks differ, mainly because checks can fail, but attacks always succeed enough to do damage. The attack roll determines the amount of damage dealt. Even in D&D, attack rolls and ability checks work a bit differently. A natural-20 attack always hits and scores a critical, but the king disregards your natural-20 Persuasion roll. He still won’t give you his crown.

Treating attack rolls and ability tests differently recognizes that the two types of checks differ in key ways.

Frequent rolls even out highs and lows

A d20 roll yields extreme numbers like 1 and 20 as frequently as middle numbers, creating unpredictable results and adding excitement. D&D swingy d20 attack rolls play well because players make far more attack rolls than other tests. The high number of attack rolls tends to even out the random swings of each roll. Characters sometimes miss, but they hit often and still contribute to the fight.

For ability checks, that d20 roll creates a different dynamic where the roll of the die weighs much more than the +5 attribute bonus of the most exceptional characters. In D&D worlds, the mighty barbarian fails to open a pickle jar, and then hands it to the pencil-necked wizard who easily opens the lid. Such outcomes feel wrong. (See Why D&D’s d20 Tests Make Experts Look Inept and How to Make the Best of It.)

Depending on your distaste for a game like D&D that adds surprises at the price of making experts look inept by routinely letting them fail easy checks, the game might play better with something like a 3d6 roll for resolving ability checks. D&D has a precedent for checks based on a bell-curve die roll. Before D&D added ability check mechanics, some gamers used this house rule: You succeed if a 3d6 roll totals less than your relevant ability score. So a PC with an ability score 11 succeeded half the time, while someone with a 17 almost always succeeded. You can quibble about aspects of this mechanic, but it made high and low scores decisive enough for these traits to show in play. A similar mechanic would never work for to-hit rolls. Characters would virtually always hit, making attack rolls perfunctory. In 2004, the third-edition Unearthed Arcana book proposed a rule variant substituting a 3d6 roll for the d20. “The bell curve variant rewards bonuses relatively more and the die roll relatively less.” A D&D-like system might find an ideal compromise by using d20 attacks and either 3d6 or 2d10 ability checks. Such a compromise would lose the elegance of a single core mechanic, but original D&D used different mechanics for everything and the game thrived, so perhaps we could adapt to two.

Rolls where nothing happens

Repeating the same attack can be fun. Even a missed attack only brings momentary disappointment; the game speeds on to another turn. In contrast, an ability check that fails may create an inconclusive result that invites another try, perhaps starting a tiresome series of attempts that go nowhere and stall the game. Many newer games try to break such patterns. “In Daggerheart, every time you roll the dice, the scene changes in some way. There is no such thing as a roll where ‘nothing happens,’ because the fiction should constantly be evolving based on the successes and failures of the characters.

“A ‘failure’ should never mean that a character simply doesn’t get what they want, especially when that would result in a moment of inaction. Every action the players take should yield an active outcome—something that changes the situation they’re in.”

D&D assumes that ability checks work using the same principles as attacks, so as with an attack, a character can keep trying the same check. For both attacks and checks, circumstances might force a character to stop trying, but otherwise players keep rolling until they get the result they want. One check just represents one attempt of what could be many, and the outcome of a roll might be that nothing happens. Roll again and hope for a 20. The process can become so tiresome that third edition invented the “take 20” rule to skip to any mathematical inevitability.

Checks that focus on intent

D&D-style games tend to treat checks and attack rolls as the indifferent physics of the game world. Imagine an omnipresent DM rolling a DC 1 dexterity check every time a creature crosses the room. (With a swingy d20 roll, that means someone like me with a -1 Dexterity modifier fails to cross 1-in-20 rooms.) Intentions, drama, and fun hardly matter. Creatures can climb half their speed, making checks every turn, until they reach the top or fall to their death.

Games like Burning Wheel break the pattern retries by making checks start with a player declaring what they intend to accomplish, and then letting a roll decisively answer whether the character succeeds at their intent. “A player shall roll once for an applicable test and shall not roll again unless conditions legitimately and drastically change.” To reach a decisive answer, the difficulty of the check depends on intent. So a test to see if a character can pick a lock becomes harder if the character wants to work quietly, and harder still if they want to finish quickly before the guards return.

This attention to intent lets a failed check result in more natural consequences than a temporary failure and “I want to take another Utilize action to try again.” Instead, something behind the door hears the tampering and opens the door. Or the guards come into view the moment the lock pops. Either way, instead of stalling at a locked door, the game races ahead. Even if the check only reveals that the character fails to open the lock, the result is decisive and the players learn the lock surpasses their skills. Instead of trying again, they must find another route. Maybe just ring the bell and bluff. The story continues.

Such decisive checks assume that the character makes their best effort to succeed under the circumstances. You can’t try picking the lock with your non-dominant hand first, so that you gain a second attempt using your dominant hand. You can’t get a second attempt by oiling the lock. Your rogue almost certainly knows more about picking locks than you; they already tried the oil.

Focusing on intent also enables one check to apply for an entire task. Burning Wheel calls this the “Let it Ride” rule. Especially with that swingy d20, a series of checks nearly guarantees a failure. The expert climber falls and the master sneak breaks wind. Letting it ride means that one roll decides whether a character reaches their intended goal unless conditions drastically change.

You might protest that a good DM can run checks this way in D&D. Exactly. That’s the brilliance of focusing on intent and letting checks give decisive results. Even though the D&D rules steer toward a different style of play, DMs can opt for a decisive approach that works better.

Degrees of success and failure

Except for critical hits and a few powers with effects that get worse “if the saving throw fails by 5 or more,” D&D tests never show degrees of success or failure. D&D started without crits and only includes them now because players love them. Few players realize that crits hurt their characters more than monsters. Monsters typically die in three rounds. If they take a crit, that makes two. PCs may take hundreds of hits and numerous crits over their career. One crit could end a long run. Fumbles used to be as common a D&D house rule as crits, but when gamers realized that the skilled warriors with multiple attacks also rolled the most natural ones, fumbles fell from favor. D&D co-creator Gary Gygax knew crits and fumbles hurt PCs more than monsters and fought to keep them out of the game.

Other games have check mechanics that do show success and failure. For example, Fate includes a range of 11 adjectives from “terrible” to “legendary” describing degrees. Many gamers love the storytelling potential of a range of potential outcomes. The challenge of such mechanics comes when game masters keep facing the task of inventing the benefits of a “superb” success and the consequences of a “poor” failure. Also, as a player who enjoys the tactical decisions of combat, I favor games where I know the potential results of my attack rolls and rarely wonder what the game master might invent.

Most RPGs with a big combat pillar tend to tabulate the possible outcomes of good and bad attack rolls. A strong attack can always deal extra damage. In the heyday of critical hits and fumbles, games included grisly tables of potential outcomes and characters took to tying weapons to their hands to avoid all the dropped swords. None of this benefited the fighters who made most of the attacks or the PCs in general, who suffered from every monsters’ limb-severing crit.

If ability checks with degrees of success and failure tax the creativity of game masters, and if crits and fumbles punish PCs more than their foes, then how can degree of success and failure work?

Daggerheart stands out for letting bad attack rolls hurt attackers, but only with mild and indirect consequences: Initiative passes to the players’ foes and the game master gains Fear points to boost monsters. The Hope and Fear points that come from good and bad combat rolls just power characters and their foes.

For most play styles, fumbles on to-hit rolls don’t work. Pathfinder 2 includes critical successes and failures for both ability checks and saves, but the game skips fumbles for attack rolls. This stands as an instance where different rules apply to different types of checks. Modern games where players can fumble attacks either tend not to feature combat or tend to have characters that make equal numbers of attack rolls.

Pathfinder tries to ease the GM’s creative load by specifying the results of critical success and failure for most saves and actions. For instance, a critical success on a save might mean that you take no damage instead of half. And a critical failure on an attempt to pick a lock means you break your tools. Nonetheless, without factoring intent into the consequences, Pathfinder has limited possibilities for outcomes. How many times will the rogue break a lockpick before they just start packing 20 extras?

Decisive checks that factor intent work better because they lead to more natural consequences and because they never stall the game with inconclusive results and a pile of broken lock picks.

Different mechanics

Draw Steel shows a state-of-the art example of attack rolls and ability checks that use different mechanics. Ability checks show decisive answers with degrees of success. Bad failures bring complications that raise tension. Attack rolls skip fumble results, but include degrees of success that replace separate damage rolls. This streamlines the attacks in a D&D-style game, and cutting perhaps 20 seconds from each of a hundred attack rolls made during a session leads to a faster pace. As for the advantages of a 3d6 bell curve versus a d20 swing, Draw Steel splits the difference with a 2d10 triangle.

How to Turn D&D’s Swingy d20 Checks Into a Feature That Can Improve Your Game

Dungeons & Dragons uses d20 rolls to randomly determine success and failure. A single d20 yields extreme numbers like 1 and 20 as frequently as middle numbers, and this shapes the game. In the real world, experts attempting routine tasks rarely fail and novices making a first try rarely succeed. But D&D tests rolled on a d20 often lead experts to botch checks and the untrained and untalented to luck into success. The d20 often makes experts look inept, defying everyday experience.

Seeking a better match with reality, some roleplaying game designers create games with core mechanics that total the results of multiple dice. This creates a bell-shaped curve of probabilities that makes the highest and lowest numbers rare, and lets players build heroes that show the sort of reliable competence we see in fiction.

Meanwhile, in D&D worlds, the mighty barbarian fails to open a pickle jar, and then hands it to the pencil-necked wizard who easily opens the lid. Such outcomes feel wrong, but with the right mindset, that swingy d20 can become a storytelling feature rather than a bug.

To start, as a DM, don’t ask the barbarian for a check to open the damn jar. “Remember that dice don’t run your game—you do,” explains the Dungeon Master’s Guide. “At any time, you can decide that a player’s action is automatically successful.” This means skipping rolls on tasks “so easy and so free of conflict and stress that there should be no chance of failure.” For best results, rate “easy” generously. Let talented or skilled characters skip the rolls where only a comical fumble would explain failure.

For knowledge and information checks, drop the roll and tell players what their characters should know. I often reveal lore based on characters’ proficiencies and background. For instance, the druid knows of the cursed trees surrounding the grove, while the dwarf knows about the flooded mine. This technique works especially well for the information players must learn to continue. Essential backstory feels like a reward for a character’s choices. Players won’t know what knowledge comes from their characters’ aptitude and what you had to reveal to advance the plot.

If everyone at the table rolls a check with the swingy d20, someone usually rolls high. In D&D, letting everyone roll certain checks practically guarantees success. The one wizard proficient in, say, the Arcana skill will seldom roll a better success than every one of the other 4 know-nothings in the party.

For a real test that acknowledges the skilled and talented characters, allow fewer characters to roll. Limit the check to characters with proficiency. This rewards the cleric proficient in religion even if their knowledge is hampered by low Intelligence.

Granting an expert character advantage reduces the chance of an unlikely fumble, and improves the chance that talent will lead to success.

  • Limit a check to the active character, possibly just the person who asked, and then grant advantage based on the party’s advice and assistance. This encourages groups to have the character most suited to a challenge to lead the way.
  • Limit a check to the skilled characters and then grant advantage based on the party’s help. I love when this enables a quiet player to gain the spotlight based on their character’s aptitude.

When someone fumbles a roll, instead of describing the failure in a way that makes the hero or monster seem inept or comical, describe the stumble so the fault comes from tough opposition or an impossible situation. DMs feel tempted to narrate bad rolls for laughs. We can narrate a 1 with a description of how someone’s hat tilted to cover their eyes and gain an easy laugh that feels fun in the moment. But too many descriptions like that turn characters into clowns and their opponents into jokes. Instead, use a 1 to describe a foe’s superhuman speed or the swirling hot ash clogging the air and stinging the heroes’ eyes. When you describe outcomes, even the fumbles, flatter your heroes and monsters.

Despite all these techniques, the d20 brings extreme numbers that create shocking failures and inexplicable successes. To cope, treat the swings as a storytelling challenge to embrace. The dice make us surrender some control, adding the risk that the story won’t go as we plan. Events beyond our control make the game unpredictable and exciting. Savor that.

“As often as possible, I like to stick with whatever the dice tell me, partly because as a DM I love to be surprised,” explains D&D lead rules designer Jeremy Crawford. “I love that sense whenever I sit down at any table where I’m DMing. I don’t actually know what’s going to happen because I don’t know what the dice are going to say. The dice can turn something I thought was going to be a cakewalk into a life or death struggle.”

The dice nudge, and sometimes shove, D&D games out of their expected course. They give D&D games a way to surprise us, and to challenge us to become more creative—to invent storytelling twists we would not have imagined without the random nudge.

Why D&D’s d20 Tests Make Experts Look Inept and How to Make the Best of It

Decades ago, I read game designer Steve Jackson explain why he swapped the d20 to-hit roll in Dungeons & Dragons for the 3d6 roll used in his alternative combat system Melee (1977). Steve considered the 3d6 bell curve so superior that he trashed the d20 without a second thought. His roleplaying games The Fantasy Trip and GURPS use 3d6 core mechanics. Then, I struggled to grasp Steve’s dislike of the d20.

Now, I understand Jackson’s disdain, but I love D&D. Like esteemed game designers such as Jeremy Crawford and Monte Cook, I find reasons to embrace the d20.

In Cook’s designer’s notes for his Numenera RPG, he describes the d20’s flaw. “Using the d20 introduces a great deal of randomness into a game. It’s difficult to use a d20 as a task resolution die and still have character aspects play a big part in success or failure without all of a sudden finding yourself using pretty big numbers.” He gives an example like this: Suppose two archers try to hit a bullseye by rolling a 20 or higher. An untrained person with a decent 12 Dexterity gets +1 and hits 10% of the time. In comparison, a 12th-level ranger trained in the bow and boasting an 18 Dexterity gets a +8, but still only hits the bullseye 45% of the time.

D&D games show this dynamic when the DM asks everyone to roll an Intelligence (Arcana) check to recognize ancient sigils, and then the brainy wizard fails while the barbarian knucklehead succeeds. That outcome may seem funny the first time, but similar scenes play frequently and can feel disappointing. Instead of rewarding the player who chose to make a character good at something, the d20 roll often makes experts look inept.

If D&D used bigger bonuses, then experts would get a boost. Suppose the expert archer gained a +25 and hitting the bullseye required a roll of 30. Now, the sharpshooter feels more like Annie Oakley. But that arrangement makes difficult tasks impossible for unskilled characters when we really want success to become rare.

Instead of using big modifiers, fifth edition’s bounded accuracy uses modest bonuses that give every character a chance of success at the price of making experts inconsistent.

Monte describes an alternative. “Now imagine that you used 2d10 instead. 2d10 gives us a more normal distribution. In other words, you end up with a much better chance of getting a 10 than a 20. Using the same bonuses, the archer still hits the bullseye 45% of the time, but the unskilled guy only 3% of the time. That makes more sense.” With a 2d10-based game, clumsy newcomers at Faerûn athletic competitions luck into fewer medals. (In one of my very first posts, I grappled with a related issue.)

This more natural range of outcomes leads game designer Steffan O’Sullivan to write, “I’m not fond of dice systems with a flat distribution. I’m solidly in the bell-curve camp.” O’Sullivan created the Fudge RPG, which became the basis for the popular Fate system. Both games use a set of four special 6-sided dice marked on two sides with a plus (+), two with a minus (-), and two blanks. “When you need to roll dice in Fate, pick up four Fate dice and roll them. When you read the dice, read every + as +1, every blank as 0, and every – as –1. Add them all together. You’ll get a result from –4 to +4, most often between –2 and +2.” No roll requires counting past 4, so even little kids add the results easily. “The fewer mathematical calculations used to figure out a dice result, the more likely you are to stay in roleplaying,” O’Sullivan writes. “So Fudge Dice were born, and I like them a lot. They’re a joy to use and don’t slow the game down at all, one of my early design goals.” The system’s bell curve makes results of -4 and +4 rare, but possible. So a +4 (1.23%) matches my real-life chance of a bullseye, while an Olympic archer scores a bullseye on any roll better than -4.

Despite the virtues of the bell curve, Monte Cook still opted for a d20 for Numenera and D&D creators Gary Gygax and Dave Arneson chose the d20 for to-hit rolls and saving throws. The d20 rolls beautifully, it generates a big range of numbers without adding, and the icosahedron feels deliciously different from the bland cubes in countless games like Monopoly. Gygax became particularly enchanted with the exotic new dice from Japan.

Most importantly, d20s yield predictable odds compared to mechanics that combine multiple dice. Monte Cook explains, “If you’re using a system where the GM has to assign a target number for a task, it’s a lot easier to do that on the fly with a d20 than, say 3d6 or 2d10. Why? Because with a d20, the difference between, say, 17 and 18 is the same as the difference between 8 and 9. They’re basically just 5% increments. With a bell curve, that’s a lot harder to figure for the GM, particularly on the fly.”

In 1974, D&D lacked ability checks. To decide between success and failure, Gary Gygax suggested that DMs estimate the chance of success, and then improvise a roll that fits the odds. A d20 roll made the math easy.

Playing D&D means learning to embrace the d20’s swings. To help gamers love the d20, D&D’s current rules architect Jeremy Crawford offered advice on the October 3, 2019 episode of the Dragon Talk podcast. “Any time the d20 is in the mix, that is a swingy die so get ready for the unexpected. What I encourage groups, players and DMs alike to do, is rather than viewing that as something to chafe against or be unhappy about, embrace it as a storytelling opportunity. Over the years, the longer I play D&D and DM D&D, the more I have come to love the unpredictability of the d20, because so often it will create moments that will challenge the DM and the players to really stretch their storytelling ability to come up with a fun reason for why this transpired. Why did the ace rogue who triggered this battle, why did she end up going last?

“When the d20 throws you a curve ball, catch it and follow through with the curve. Just see where it leads you rather than saying, ‘this is dumb’ or ‘this isn’t how it should play out.’ No, in D&D, what the d20 does is really showing how this is going to play out. Let’s ride it and see where this craziness goes.”

If I were magically transported back to a version of 1974 that somehow lacked Gary Gygax and Dave Arneson, would my attempt to bring dungeons and dragons to the world use a d20? I might choose Fudge Dice, but I would never stop giving those new icosahedrons from Japan forlorn looks.

Related: D&D and the Role of the Die Roll, a Love Letter
When You Describe Outcomes, Flatter Your Game’s Heroes and Monsters
In D&D, Letting Everyone Roll Certain Checks Guarantees Success, So Why Bother Rolling?