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: