This will start off with a bit of a quick review of the advantage/disadvantage system, so feel free to skip down a bit if you’re already thoroughly familiar with that.
In 5th Edition, various circumstances and abilities grant either advantage or disadvantage to a character attempting an action: If you have advantage, you roll 2d20 and keep the higher result. If you have disadvantage, you roll 2d20 and keep the lower result. If you have both advantage and disadvantage, they cancel out (and you just roll 1d20). And they do not stack (so no matter how many things are giving you advantage, for example, you still only roll 2d20 and keep the highest, not 3d20 or 5d20 or 10d20), which also means that even one factor granting advantage will cancel out any amount of disadvantage (and vice versa).
There are several benefits of the advantage/disadvantage system compared to giving circumstantial modifiers to the die rolls:
- The modifiers you’re rolling against are not in constant flux, reducing the amount of in-game calculation required.
- It is viscerally pleasing and immediately rewarding to roll 2d20 and take the higher/lower result. It’s fun to do and you can literally see how your advantage benefited you or your disadvantage cost you by looking at the result on your gained/discarded die.
- It helps maintain the “bounded accuracy” of the system; advantage helps you, but you can still only get die results of 1 to 20.
- “Advantage” and “disadvantage” are incredibly useful terms of art, which designers, scenario writers, and DMs can quickly and efficiently use for any number of purposes. For DMs, in particular, they provide a very simple way to make a fast ruling.
The reasons for not allowing advantage or disadvantage to stack are:
- To maintain the simplicity of that fast, efficient DM’s ruling. Once you’ve determined that something in the situation grants advantage, for example, you don’t have to keep thinking about all the other things that might grant advantage: You have advantage. Move forward. Roll the dice.
- You don’t need complicated stacking rules, nor do you need to allow abilities to stack in potentially absurd ways. This removes one vector by which an RPG system filled with myriad options can suddenly break from the unexpected combination of those options.
- There are some mathematical effects of allowing advantage to stack multiple d20’s into a single roll, the most notable of which, in my opinion, is that your percentage chance of scoring a critical hit radically expands. (This last point is debatable, however, as many would argue that this is perfectly reasonable if you’re enjoying a massively advantageous situation. It also only applies to actually stacking additional dice, but not to the scenario in which you stack all advantage and all disadvantage and then compare the totals to see whether advantage, disadvantage, or neither applies.)
This system has one additional advantage (pun intended) that I want to call specific attention to: The simple, clear-cut mechanical concept of “advantage” also encourages players to engage creatively with the game world in order to create fictional positioning that grants them advantage.
Another example of this that I’ve seen in actual play is Numenera‘s concept of an “asset” — on any given task, PCs can have up to two assets, each of which shifts the difficulty of the task by one step. The first asset “slot,” so to speak, is often occupied by having the right tool for the job. The second asset slot is usually dependent on having some sort of advantageous situation in the game world, and this naturally results in players seeking to create those in-world circumstances that will give them an asset on a task.
In both cases, the clear-cut term of art coupled to the specific fictional situation in the game world reinforces the fiction-mechanics cycle. The mechanic thus, almost paradoxically, encourages players to engage in the game in non-mechanical ways: It’s not enough to just “play your character sheet” by saying “I hit the orc with my +6 attack bonus,” because the mechanics are no longer confined to the bonuses on your character sheet.
Arguably, of course, you can get the same benefit from any system that allows GMs to assign situational bonuses and penalties. But in actual practice, the clear-cut mechanical concept with a term of art attached to it provides a common framework. People just talk about and think about “advantage” and “assets” in ways that they don’t talk about and think about a miscellanea of +1, +2, or +5 bonuses.
THE PROBLEM
Speaking of actual practice, however, this final — and arguably most important — aspect of advantage tends to frequently disappear at the table.
The problem, ironically, is the very versatility of the system. Because advantage is such an easy mechanical hook to use, the designers of the game have used it to model all sorts of things. It’s hard-coded into everything from class abilities to spells to magic items. For example:
Dwarven Resilience. You have advantage on saving throws against poison, and you have resistance against poison damage (explained in Chapter 9).
Or:
Beacon of Hope. This spell bestows hope and vitality. Choose any number of creatures within range. For the duration, each target has advantage on Wisdom saving throws and death saving throws, and regains the maximum number of hit points possible from any healing.
Or:
Boots of Elvenkind. While you wear these boots, your steps make no sound, regardless of the surface you are moving across. You also have advantage on Dexterity (Stealth) checks that rely on moving silently.
Because advantage doesn’t stack, however, tension is created between the designer’s utility and the DM’s utility: If a character has hard-coded advantage from equipment or racial abilities or whatever, the DM immediately loses the ability to meaningfully model the game world through advantage and the player is simultaneously discouraged from engaging with the game world in order to create favorable circumstances.
This is not a desirable outcome: Basically every time the game hard-codes advantage in this way, it makes the game less interesting in actual play.
Numenera recognizes the same basic problem, which is why it provides two asset “slots.” The solution is not quite so straightforward for 5th Edition because there are so many pieces of equipment, for example, that provide identical forms of advantage, that simply providing two slots will simply create min-max builds that stack multiple advantage and still shut down situational creativity (because both slots will already be filled).
But we can find a solution, I think, through parallel thinking. And by simply cutting straight to the heart of the matter.
SITUATIONAL ADVANTAGE
Situational advantage is any advantage which is derived from a character’s immediate circumstances; particularly and specifically those cases of advantage resulting from characters taking actions or positioning themselves in order to create specific situations which grant them advantage.
Situational advantage, and only situational advantage, stacks with other advantage:
- If you have hard-coded advantage (e.g., the advantage against poison damage from dwarven resilience) and situational advantage (e.g., the character manages to dilute the poison before being forced to swallow it), then you roll 3d20 and take the best result.
- One source of disadvantage can cancel EITHER all hard-coded advantage or all situational advantage, but not both. (So if you have all three, you’d still have advantage and roll 2d20 while keeping the best result.)
- If you have two or more sources of disadvantage, then they will cancel both hard-coded and situational advantage. (You would simply roll 1d20 and resolve the action check normally.)
Note that not all forms of advantage appearing in the rulebook are necessarily hard-coded. Some describe situational advantage. (The optional rules for flanking, for example.)
What about advantage from spells? Is the advantage provided by a spell situational? There is a potentially simulationist argument that they are (or perhaps that some subset of them are, although that way probably lies madness). But the primary meta-game point of all this is to encourage players to think creatively as they engage with the game world instead of just throwing a prepackaged block of mechanics at a problem.
And a spell, after all, boils down to a prepackaged block of mechanics.
So if I had to make an ironclad rule, I would say that advantage from spells is always considered hard-coded advantage.
Fortunately, the entire point of situational advantage is to prevent hard-coded rules from disempowering the GM. So I will by happy to override this ironclad rule whenever players think creatively in order to create situational advantages from their spells. For example, by using a create food and water spell to water down the poison before it’s fed to the dwarf.
Don’t take it as gospel, but I’ve heard that Shadow of the Demon Lord’s version (+/- d6) was the original plan, but was nixed by Wizards. I’ve often pondered swapping in Demon Lord’s system in 5e game.
Your thoughts?
Would Situational Disadvantage exist as well?
It seems like an easy assumption to make that it would exist, but you don’t mention it in your article. Only that two disadvantages actually do stack to beat both hard-coded and situational advantage.
I’m imagining a situation where a PC has hard-coded disadvantage (like blindness), and they want to try something beyond the scope of their situation (like pull off a crazy stunt while attacking).
The interactions between hard-coded/situational advantage/disadvantage seem like they could get… messy. Do you think situational disadvantage should not exist?
@WhereIsMyWizardHat: I haven’t played Shadow of the Demon Lord, but one of the things you’d want to think long and hard about is the fact that you’re breaking the bounded accuracy which is a central design principle for 5E. Advantage is basically an entire mechanical substrate that specifically lets you say “you’re more likely to succeed cause of this, but it doesn’t fundamentally transform what you’re capable of.” It’s a view of the world that says a really good tool makes it easier for you to achieve at your skill level, but doesn’t turn you into a maestro if you weren’t already.
There’s also the fact that you’re adding an extra step of arithmetic to the resolution. It’s not a huge problem or anything, but it’s just a little bit of extra friction. I’ve come to appreciate consistency in dice modifiers (particularly in frequently repeated rolls) in part because it’s like practicing your multiplication tables: When you repeatedly attack with a +7 or +15 or +4 bonus during a session, your brain starts wiring up and very quickly knows what the result is off of any given d20 roll. If you’re constantly changing the modifier you’re using, you have to do the calculation every time.
In recent years I’ve also become a significantly larger fan of systems in which the result on the die is immediately, viscerally understood. That’s not true in 5th Edition generally (because you have to add a modifier to the die roll to get a result), but it is narrowly true of advantage/disadvantage in the sense that you can immediately see the two dice results and KNOW what effect advantage/disadvantage had.
With all that devil’s advocacy aside: Sounds like fun.
@tea: I gave it some thought, but generally speaking it’s not so much that situational disadvantage doesn’t exist; it’s that hard-coded disadvantage is vanishingly rare compared to hard-coded advantage. Maybe some cursed items give disadvantage? But other than that, disadvantage is overwhelmingly the result of specific circumstance.
(You mention blindness, for example, but PCs who are actually permanently blind instead of being merely situationally blind would be extremely unusual, right?)
Also: The primary goal is to encourage players to seek situational advantage. This is often done by putting an opponent at a relative disadvantage, but you still tend to model that giving mechanical advantage to the character seeking it. So even in the rare case where someone is carrying around some hard-coded disadvantage, such efforts probably won’t be discouraged.
There may be some odd corner cases where you’d try to set up disadvantage for another character in a situation where you’re not directly participating in the action AND that character already has a hard-coded disadvantage. If that were to come up, I’d say a GM should go for it if it seems convenient.
But, as you note, the interactions between situational advantage and situational disadvantage seem to get… messy. So probably easier to treat it as a rare one-off special ruling if you do it at all.
It is worth noting that the benefit of stacking advantage rapidly falls off. Propability wise going from 1d20 to 2d20 and picking the highest/lowest makes a much greater impact than going from 2d20 to 3d20, etc.
Of course if the players don’t know that they might still experience the thrill of added advantage, but mathematically speaking it isn’t very exciting.
“The primary goal is to encourage players to seek situational advantage. This is often done by putting an opponent at a relative disadvantage, but you still tend to model that giving mechanical advantage to the character seeking it.”
Perhaps this line can be extrapolated into a method of play at the table without changing any rules. When a character creates a Situational Advantage but the character already has a hard-coded Advantage, you rule that they’ve forced Disadvantage on their opponent.
So, in the poison example, the dwarf player says, “my dwarf gets advantage to resist the poison AND we have diluted the poison with water,” and then the DM says, “great! your situational advantage has reduced the DC by 5, and you still roll your 2 dice for advantage.”
I think this system can cover pretty much every situation, still promotes creatively engaging with the world, and prevents confusion about two different types of advantage. The DM needs to be diligent in their transparency, though. They need to reinforce that this is a consistent effect the players can seek out.
Perhaps there can be a term for it that isn’t really a “rule” but a colloquialism. “Alright everyone, I’ve already got Advantage. How can we Force Disadvantage upon our enemies?”
I like it as a houserule for D&D 5e games.
Interestingly enough, Pathfinder 2nd Edition just came out and, while it doesn’t use the Advantage/Disadvantage mechanic and isn’t committed to “bounded accuracy,” limits bonuses and penalties to: circumstance, status, item, and untyped. So it allows for a “situational advantage” (circumstance), advantage from gear (item), and advantage from a spell (status). But it does employ pluses and minuses and brings up the question “do these stack?”, which brings in complexity and so there’s that.
“…providing two slots will simply create min-max builds that stack multiple advantage and shut down”
It looks like there’s something missing at the end of that sentence.
How would this system interact with the Elven Accuracy feat in Xanathar’s? In short, when a character with this feat attacks with advantage, they roll 3d20. Would situational advantage add an additional die to this, or would it cap out at 3d20?
@Ronald Cruz, the bonus types in Pathfinder are all frequently found in hard-coded rules, and so they are closer to what would happen to D&D if you used Numenera’s asset slots than what situational advantage is trying to do. Pathfinder players just create min-max builds that stack multiple bonus and shut down situational creativity (because all slots will already be filled).
Also, the lack of a clear-cut mechanical concept representing situational advantage in favor of an arbitrary numerical range of circumstance bonus disincentivizes both players and GMs from straying from hard-coded rules.
This is a good post, and serendipitous, since I’ve been thinking a lot about advantage in 5th edition recently. I think your ‘3d20’ solution is probably the most elegant one as far as stacking advantages goes.
I think there’s a larger problem with advantage as a prod to fictional positioning, though, which is that the reward is often tiny compared to the opportunity cost (unless you’re just using terrain to your advantage). Do I really want to spend my action to get a ~50% better chance to hit? I’ve been toying with different solutions to this problem, including things like making attacks made with what you’ve helpfully defined here as ‘situational advantage’ deal critical damage and/or impose a condition.
How would you rule when a player makes a skill check, has a relevant tool proficiency and the tool itself?
@gorice: For combat, I often find that situational advantage (and the related asset concept from Numenera) will manifest before combat starts. That you set up the conflict to give yourself an advantageous situation. That sort of sidesteps the opportunity cost problem. Similarly, taking an action to put a teammate into an advantageous situation. Or framing your movement.
This also pays dividends outside of combat, though. And often you get more far more interesting results in that case.
@Jacey: I’d probably go with 4d20.
There is a big problem mathematically: using multiple advantages you get a non linear advantage but the difficulty of your action is still linear (check how the mean and the standard deviation change by adding dice)
https://anydice.com/program/173ec
The system you suggest is basically CoC7 system, where hard challenges and extreme are given as 1/2 and 1/5 of the rating. In a normal game getting a 1/5 would be really hard (something between 1-12% chances in many cases), but 2 advantage dice increase the probability to do 1/5 to around 20%, a couple of dice more and it’s 40%.
CoC has this nonlinear difficulty embedded in the system, and if you try to play you can see that having a flat modifier (like -20% or +20% like in Delta Green) wouldn’t work well in an advantage system that has multiple cumulative advantages.
@uriele: The system who suggests? I’m not sure what you’re trying to say.
@Malthe: Moving from 1d20 to 2d20 is roughly a +3 shift and gives you an additional +4.75% chance of critting. Moving from 2d20 to 3d20 is a +2 shift and gives you +3.5% chance of critting.
It does tail off. But the shift is still significant. (Generally more significant than, say, having a +1 sword in previous editions.)
@Justin Alexander
Oh, absolutely, there’s a lot you can do with the way you approach the battle. Personally, I like the actual blow-by-blow stuff to be a bit more dynamic, though, and I feel like some combat actions (‘help’, non-damaging attacks) are supposed to encourage this, but the weakness of advantage makes them too situational for my taste. I guess this is kind of a different topic, though.
So hey, I’m commenting on an ancient post and nobody will ever see this, but it’s interesting so what the hell.
I think at the point where you’re getting to 3d20 or 4d20, it’s getting a little unwieldy and you start to lose the simplicity that’s at the heart of 5e’s advantage mechanic. The RAW version is a very nice balance between simulation and narrative and – as you say – provides a nice framework for how you think about a situation.
There’s a variant I’ve tried out in a few one-offs that I think keeps that simplicity better, and provides another useful framework for how to think about things. The idea goes that sometimes, the situation favours particular outcomes – sometimes it favours one side, sometimes the other, or sometimes fate is for or against a particular course of action. In game terms, I use ‘fate is with you’, ‘fate is against you’, or ‘fate is with/against ‘. When fate is one someone’s side, multiple sources of advantage will counteract any disadvantage. When fate is against something, multiple sources of disadvantage will counteract any number of sources of advantage.
In concrete terms, if one group spends a significant effort preparing a perfect ambush and are undetected, then fate is with them for that fight. If there are seals for an ancient, imprisoned deity then as soon as any of them are broken, fate is on the side of any action that damages more seals as the entity’s power and will begin to leak out slightly. Fate is on the side of healing and protection within the aura of a particularly powerful (immovable) relic.
The idea is maybe once or twice a session, there’s an opportunity for one side of a conflict to have fate on their side, but it takes player action to trigger – either to put the right situation in place to take advantage, or to prevent their opponents from doing so to avoid it. In most general cases, the party knows immediately that things are looking good or bad. If it’s something more subtle, I tend to clue in a few party members that something is up (Anyone with ties to luck (Divinier Wizard, Halflings, anyone with the Lucky feat) or a very high passive Insight), and let them know the effect the first time it triggers.
Haven’t tried it in a full campaign yet, but the players liked it – I’m planning to use it the next time that group starts a new game.
The Numenera “asset” or slot is an interesting way to think about it. It’s interesting to me that the 5e “proficiency bonus” is a binary on/off bonus that can be turned on by an infinite number of options, but they all have the same level-based bonus so there’s a cap on the min-maxing. My players have gotten into using variant abilities with their skills, so that forms another “slot” with a different kind of decision. And then there’s advantage/disadvantage, and potentially situational advantage/disadvantage. Is it possible to get too many “slots”?
It feels to me like those “hardcoded” advantages and disadvantages should really be static +5 or -5 modifiers, but maybe WotC was trying to sell the new idea of advantage.
To be honest, I’m not sure whether category separation is truly needed in 5e. Bounded accuracy and the nature of dice vs flat bonuses put an inherent soft cap on stacking advantages. The chance that any one die will roll higher than the others decreases based on the number of dice already in play.
Past a certain point, it just isn’t worth it to spend yet more time embellishing that ambush, or expend that third buff spell on the same person.
This isn’t a perfectly elegant solution, since you still have to weigh the total of advantage/disadvantage to determine the net effect, but it’s still simpler than most other systems. I wonder why the designers didn’t include it as a variant rule.
This is very useful for me, as I may be running Gateway soon. It’s a free hack of 5E where adv/disadv is the primary mechanic (so that an absentminded wizard would have advantage on spell, research and intelligence checks but disadvantage on Strength and hand-to-hand fighting checks. Thanks!