Rolling more dice is a good measure of advancement in D&D. When we roll more dice, we feel like our characters are performing well. This natural tendency leads us to knee-jerk a little bit when we see something like “super advantage” come out of the Elven Accuracy feat in Xanathar’s Guide to Everything.
Elven Accuracy gives you “super advantage” via a mechanic that lets you select the best of three dice rolls when you have advantage on an attack:
Many players recoil at the hit certainty imposed by rolling three dice. Back in March, I wrote about the strength of the Sharpshooter feat. While players don’t think Elven Accuracy is as “broken” as Sharpshooter, there were a significant number of players who thought it was:
Marginal Utility
The truth is that the “super advantage” part of the feat doesn’t do that much. That’s because already having advantage is normally good enough. Since “super advantage” only triggers when you already have advantage, you’re only getting the extra bonus above advantage, which will always be less than the bonus you get from getting advantage in the first place.
In economics, there is a concept called “marginal utility,” which is the additional satisfaction a consumer gets from consuming one more unit of a good or service. Almost universally, the amount of satisfaction from getting the same thing a second time is not as good as getting the first one. This is known as the Law of Diminishing Marginal Utility.
The same is the case with advantage. The more and more dice you roll, the less each one matters. Each additional advantage die has less marginal utility. You can see this in action on this chart:
For example, let’s say you need to roll a 10 to hit. You have a 55% chance of rolling a 10 or higher. With advantage, you have an 80% chance–a 25% boost! With “super advantage,” you have a 91% chance–only another 11%! So in this example, “super advantage” makes less than half the difference that just getting advantage in the first place. Nothing to sneeze at, but certainly enough to help you consider investing that feat elsewhere.
Running the Numbers
Naturally, the power gamer in all of us (even those with a roleplaying heart as pure as the driven snow) wants to see how these crazy toys stack up together. I’ve updated the Sharpshooter Shot Chart released in last month’s article to include Elven Accuracy (the grey dashed lines) plus a few other updates:
ThinkDM 
This – this is amazing. Kudos on the graphs and the explanation. I bow down to your superior game analysis!
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Its lame, how often do you get advantage on a shot?
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You can get advantage extremely often if you plan your character properly and work with your fellow players.
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Definitely! There’s a little push and pull between player skill and DM generosity, but advantage shouldn’t be super rare. Just ask for it!
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If you use UA material, Rogues can get Advantage every turn with Aim. Even without, there is Swashbuckler and Assassin. In fact, Sharpshooter is incredible with Gloomstalker 3/Assassin x for alpha strikes.
It takes awhile to come online (level 7 minimum) but a GS 3/A 4 Elf on their first turn against a foe that hasn’t acted yet has an attack that looks like this: two 3d20+Proficiency+Dex+2 (Archery) Attacks, with the first dealing 1d8 (Longbow) + 2d6 Sneak Attack + Dex damage, and the second doing 1d8+Dex+1d8 (Piercing). Plus you can pop off Hunter’s Mark to add 1d6 to both attacks (putting you only 1d6 behind a pure Rogue’s Sneak Attack), or Zephyr’s Strike to give you Advantage +1d8 damage any time after the first turn.
You’re basically never going to miss and will be rolling tons of dice with crits.
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Hi Harold!
Based on what I’ve heard, I would be surprised if Aim made it to print. I wouldn’t jump into too many balance equations without seeing where that pans out.
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Very good analysis! If I may say, one thing worth mentioning s is how that particular example (rolling a 10) scales throughout the various required dice rolls to hit. That the marginal utility of EA is considerably lower than that of advantage doesn’t hold true at higher dice rolls.
Starting with the 10 you used as an example, it goes 55%/80%/90% – so 25% gain from advantage, 10% gain from Elven accuracy. So the Elven accuracy bonus is less than half of what you get compared to just having advantage (as you state above).
Yet, to roll 17 or better is 20% / 36% / 49% (regular vs advantage vs elven accuracy). In that example, the marginal utility to hit from advantage is 16% vs another 13% from elven accuracy. That’s about 80% of the marginal utility from just advantage.
On the higher end of the scale, the marginal utility of the additional dice from elven accuracy is pretty close to the marginal utility of advantage. To roll 18 or better would be 15%/28%/39% (so a 13% gain from advantage, and 11% additional from EA).
To roll 20, we can see the approximate chance of critting going from 5% , to 9.75 to 14.26% with elven accuracy, nearly triple the base 5%. To roll a 20, the marginal utility of elven accuracy is almost 95% of the marginal utility from advantage.
Consider an elven fighter champion with a crit range of 18-20. With normal attacks: 15% crit chance. At advantage: 27.75% (Gain of 12.75%). With Elven Accuracy: 38.59% (Gain of 10.84%). That’s going from 1/4 of the time you’re critting to almost 1/2 of the time (assuming you have a reliable means of gaining advantage) .
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