Our Ability Check Toolbox

by Mike Shea on 5 November 2018

The more we focus on the story of D&D, the more ability checks become the main mechanic as characters interact with the world around them. Asking for checks and getting the results sounds easy. Ask the player for a roll, add the appropriate modifiers, and match it up against a DC. Simple.

When we're running our game, though, it isn't always as easy as it sounds. It isn't always clear how we should call for checks, to whom, and how we should adjudicate the results. What if a player does a particularly good job roleplaying an encounter with an NPC but rolls poorly on their persuasion check? Is all that good roleplaying lost? What about when a character wants to examine a door, rolls a 2, and everyone else at the table wants to jump in and check the door as well?

In today's article we're going to dig deep into how we use ability checks in the story of our D&D games.

A Summary of Ability Check Options

This is a big article so here's a summary.

Understanding the Rules As Written

Whenever we're going to dig deep into any mechanic in D&D, it's best to read the rules and understand their intent. In the case of ability checks, we have chapter 7 page 173 in the Player's Handbook and chapter 8 page 237 in of the Dungeon Master's Guide to give us the written rules and some solid advice on how best to use ability checks. If you're going to monkey around with ability checks or find that things get confusing at your game, spend a few minutes reading both of these sections to reinforce how the designers intended for ability checks to work.

One thing of note, particularly for DMs who have played older versions of D&D, there are no skill checks. In the fifth edition of D&D, there are only ability checks. Skills are subjects in which characters are proficient and add to an ability modifier when the circumstances allow it. This sounds pedantic but the distinction matters, particularly in the vocabulary of the rules.

These sections in the Player's Handbook and Dungeon Master's Guide give us the basics of using ability checks including group checks, aiding another character, and using advantage and disadvantage based on the circumstance of the check. It's worth reading and refreshing ourselves on these rules regularly, particularly once we've seen how they actually play out for the group at the table.

The Random Chances of the World Around Us

The real world around is is constantly and continually moving based on random chance. Very likely the reason I am writing this and the reason you are reading it are based on very slim random occurrences that happened over our lives and the lives of our ancestors. When we interact with the world around us, random chance plays a big part in those interactions as well, even if we don't see it or choose not to.

The same is true in the world of our D&D games. In the Dungeon Master's Guide, we're given the advice that we need not worry about asking for ability checks when the task being done is either so easy that it's almost assured or so hard that it's nearly impossible. There's another way to think about this, though, and it's by considering how much randomness exists in the situation itself.

If the characters are talking to a town guard, maybe there's randomness in the response of that guard. Maybe he ate something bad earlier that day or got in a fight with his husband before work. Maybe we want to account for that potential random circumstance when our charismatic sorcerer decides to ask him about the secret tunnels beneath the ruined watchtower.

But maybe we don't. Maybe, for the sake of the story, its just easier of the guard tells the characters what they want to know. Regardless of any digestive or domestic issues the guard has, he's still likely to tell a charismatic sorcerer about the tunnels. We don't need to roll for this.

Page 236 of chapter 8 of the Dungeon Master's Guide has a whole section called "The Role of Dice" that discusses when DMs should consider rolling or ignoring dice. The section called "The Middle Path" likely offers the best option: use the dice when a bit of randomness makes sense for that situation or ignore it when the characters approach the situation in a way that makes failure unlikely.

It's important for us to understand why there is a random component when it comes to interacting with the world overall. This randomness isn't there to take some excellent roleplaying and throw it away on a shitty roll. It's there to help the world feel as unpredictable as any realistic world would feel. It's also there to make the story more interesting. If everything were simply comparisons between static ability scores and difficulty classes, we could predict every interaction before it occurred (hello Leplace's Demon!). With the roll of the die, mysterious things happen and that's fun for both players and DMs alike.

How we inject this randomness into our games and how we tweak it based on the context of the story takes some deeper understanding.

Passive Checks

There's a whole interesting discussion to have about passive checks; particularly how passive perception and passive insight work. Jeremy Crawford talked about this on a previous episode of Dragon Talk. Here's a clip from the episode where he goes into details.

In short, passive scores (perception and insight) are always on as long as you're conscious. Players don't get to say that they're using it. Passive perception is intended to be the floor of a character's perception. They might not notice anything specific but they'll know something is going on. If a player rolls perception, they might roll lower than their passive perception but the passive perception is still going on. Anything they would see with that, they'd see anyway.

We can use passive scores for just about anything if we want to but they're most likely to be used for these sort of "always on" skills. As mentioned above, if we feel like the random elements of a situation don't exist in a particular situation, we can opt for a static check on anything. If a rogue has +7 to stealth we can consider it having a general stealth of 17 if they're sneaking through a whole area and we don't want to roll on it all the time.

We might use passive checks instead of rolls in the following circumstances:

DM Rolls and Hidden Checks

There are times when the results of a situation might be a mystery to the characters regardless of a success or failure. The ability to detect a trap, for example, might be known or not regardless of the results of a roll. Yet when we ask a player to roll to detect a trap, they will know the result because they can see the result.

Instead, we might ask for a character's Wisdom (Perception or Investigation) bonus and make a hidden roll to see how it goes. This gives some mystery to the results. If they detect the trap, they know it's there. If they did not detect a trap, though, it could be because there isn't one there or they missed it. That's exciting.

There aren't many circumstances where we'd roll an ability check for a character and keep the results hidden but it can be useful and fun when it does happen. Here are a few circumstances when rolling a hidden check might be appropriate:

This technique can be fun but should be used sparingly. It's almost always best for players to roll their own checks.

Awesome Roleplaying, Poor Rolls

Sometimes, and we can see this in a lot of streaming games like Critical Role, players do quite a bit of awesome roleplaying when interacting with an NPC. Sometimes, however, their character actually isn't particularly good at that type of interaction. The character has an awesome bit of dialog intimidating the goblin but has an intimidation bonus of -1.

Sometimes we might ask for the check after such a narrative exposition and then see a terrible roll come up. All of us know, based on what was actually said, that it should have gone better than that.

There are a couple of ways we can handle this. First of all, we're within the intention of the game to offer advantage to the player for a fine bit of roleplaying. We can even give them inspiration if they want to hang on to the advantage for another check.

We can also lower the difficulty class on the fly based on the particular approach that was taken with the NPC. We might even use our shades of gray on the roll to turn a bad roll into an interesting divergent path in the situation.

We might even let the roll go away completely and, based on the awesome roleplaying, determine that there's basically no way the interaction will go against the character when they take the approach they're taking. No matter what, we are not slaves to the dice. If the approach and the situation are stronger than random chance, we can judge it a success and move forward.

Full Table Rolls

Invariably we sometimes get into a situation where a character wants to spot something, announces their intention to look around an area, rolls a 2, and then the whole rest of the group jumps in and wants to make the same check.

This can happen in both wide circumstances, like keeping an eye out for monsters while resting or something small like checking a door for traps. When the players see another player fail a check, they want to leap in to make the same check.

The circumstances of such a roll matter a lot in how we adjudicate this. We might, in our minds, have a clear idea that only one character may see or miss seeing such an event only to realize that if everyone tries, someone is bound to make the check.

If the task at hand is something only one character can reasonably do, we can simply veto the checks when the rest of the group wants to roll. We might argue that only that one chance could work and subsequent attempts won't succeed. Other times, however, we might shrug and go with the group check.

Here are some circumstances when only one character can reasonably perform a check:

And here are some example circumstances when a whole group can reasonably check.

If we do find circumstances where the whole group can participate, we might instead call for a group check. See page 175 of the Player's Handbook for details. We use a group check when the whole group acts together and succeeds or fails together. The most common group check is the group stealth check to avoid being seen as a group travels through an area but we can use it in other circumstances too. In a group check, all participants roll for the check and more than half of them must succeed in order to succeed at the roll.

If things seem too easy when the whole group would roll on a check, we can use the group check to even things out a bit.

Full Table Failures

Sometimes we want to pass some information to the characters and we ask for a full group check expecting that someone will pass. Sometimes, however, the dice work against all of us and no one succeeds. If the information was vital, we might find ourselves stuck in a corner of the story. We expected someone would pass. Now what?

Even when we're calling for a group check in which only one member of the group must succeed, we must be ready to handle it if no one succeeds at all. In these circumstances it might be best to give the highest rolling player the required information and "fail forward" with a complication of some sort such as giving away their position or not noticing the arrival of another group of creatures before it's too late.

Only Those Trained Can Succeed

The fifth edition of D&D expects that all checks are "ability" checks, not "skill" checks. Thus, when a DM calls for a check, they ask for an ability like "give me a wisdom check" to notice something coming closer in the distant sky. We might also tag on a skill with it and say "give me a wisdom check and add your proficiency if you're trained in perception". I imagine most DMs skip this and go straight to "give me a perception check" and players know to roll flat wisdom if they aren't trained.

One way to ensure that an entire group doesn't try a particularly narrow skill is to ask for only those trained in the skill to check. For example, understanding arcane runes protecting a vaulted door might require that it be checked only by those trained in Arcana. Understanding the intricate information stored in a religious text or recognizing the origin of a buried statue might require someone trained in Religion.

Requiring proficiency in a particular skill goes outside the bounds of the intended D&D rules, but it is a good way to make those proficiencies count during the game. We might stack on other backgrounds, races, or classes onto this list as well. If the characters come across a mystical tome, maybe only those trained in Arcana or those able to cast spells can attempt to decode the book's secrets using their spellcasting ability score to understand it. Perhaps only someone trained in Religion can recognize the ancient buried statue except for dwarves who might recognize that the statue is of a dwarven deity lost long ago.

Here are some example circumstances where we might only ask those who are trained to make a check:

Again, this method for ability checks goes outside the expected rules and, as Jeremy Crawford says, it should be used sparingly.

Offering Advantage for Character Traits and Backgrounds

It's always nice to reinforce a character's interactions with the world through that character's race, class, background, or any other trait of the character that gives the character an advantage in a particular situation. In these circumstances, we can give a character advantage for a particular check based on this trait.

If the characters are examining an ancient fresco buried underneath centuries of moss, the high elf character might get advantage on the check since the fresco depicts elements of the ancient elven struggle between Corellon and Lolth.

The Dungeon Master's Guide specifically discusses when to use advantage and disadvantage on ability checks. Page 239 includes circumstances when one or the other makes sense with one particularly interesting statement: "Consider granting advantage when circumstances not related to a creature's inherent capabilities provide it with an edge."

When a rogue is disarming a trap or picking a lock, we don't give them advantage for being a rogue. Their proficiency is already wired into being a rogue. Picking locks and disarming traps is what rogues do. We already know that barbarians are particularly athletic, they don't get barbarous advantage for bending bars or lifting gates. They actually get it anyway if they're raging at those vexing bars.

Backgrounds already offer skills so we might think of that as an inherent capability already but if the details of a background can aid a character beyond a skill proficiency, we can consider that enough to offer advantage on the check.

Here are some examples where we might offer advantage on an ability check based on a particular trait of a character.

Describing Aiding and Guidance

The aid another action is a great way for two characters to work on a problem with one of them giving advantage to another. The most common problem I've seen with this is that the player of the aiding party grabs a d20 and rolls without thinking about the fact that they aren't the ones supposed to be rolling. If this happens, we can tell the partners that this second roll counts as the advantage roll and add whichever modifier is higher between the two characters.

We can apply a small cost to this aid as well by asking the player to describe how they're aiding. This is a nice trick to get players into the story. It isn't enough for them to say "I'll aid them", the question is how they'll offer that aid. Fun stories can come from such questions.

The same is true with the cleric's spell guidance which offers 1d4 to any ability check. When a cleric casts this spell, we can ask the player to describe what that aid looks like. Is it a holy light that fills in the nooks and crannies of a difficult lock? Is it a small glowing halo that surrounds the rogue as she talks her way past the town guards? Is it a tiny glowing light in the eyes of the wizard as she decodes the magical glyphs embedded in the wall?

Getting players to answer these in-game story-focused questions is a great way to get them outside of their character sheet and into the world you're creating together.

Ability Checks: The Primary Mechanic between Players and the World

When we think about it, ability checks may be the biggest mechanic of D&D. In our more story-focused games, these ability checks guide nearly every challenging interaction between the characters and the world around them. The basic mechanic of ability checks; rolling a d20, adding a modifier, and matching against a difficulty class; seems so simple but how we actually implement these checks into the game can have a big impact in how the game is played and how it turns out.

Read the rules, see how they play out at your own table, and build a toolbox of methods for calling for and using ability checks in your own game. Let these checks act as the chaotic vehicles for the awesome stories that unfold at your table.

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