How do you do advantage/disadvantage?

[Ivor_The_Mad]

Hi Playground I'm back (sort of)

I was wondering how you guys do advantage and disadvantage. I just roll twice and take the highest or lowest accordingly. I don't have the players handbook so I don't know it this is how I should but I like doing it this way. One of my friends was telling me that for disadvantage you subtract 5 from the roll. So now I'm curious to see how other people do it / what is more common.

[ciarannihill]

Hi Playground I'm back (sort of)

I was wondering how you guys do advantage and disadvantage. I just roll twice and take the highest or lowest accordingly. I don't have the players handbook so I don't know it this is how I should but I like doing it this way. One of my friends was telling me that for disadvantage you subtract 5 from the roll. So now I'm curious to see how other people do it / what is more common.

You're correct. You roll 2d20 and take the higher roll in the case of advantage or the lower one in the case of disadvantage. The +/- 5 thing is a shorthand for the approximate average change in roll result from advantage/disadvantage.

It is not the mechanic, it's a way of assessing the approximate value of granting advantage in a scenario, and it can be useful for a DM or when theorycrafting a build, but it's not a super important figure other than that.

[mormon_soldier]

For either, you roll twice and take the highest (advantage) or lowest (disadvantage). Subtracting 5 is for passive checks, usually perception. There's no roll involved, so the modifier simulates the average effect.

[PhantomSoul]

RAW, the add/subtract 5 rule is how you adjust a passive score (e.g. passive perception), but otherwise you just roll twice if it isn't a passive check.

[KorvinStarmast]

I was wondering how you guys do advantage and disadvantage. I just roll twice and take the highest or lowest accordingly. I don't have the players handbook so I don't know it this is how I should but I like doing it this way. One of my friends was telling me that for disadvantage you subtract 5 from the roll. So now I'm curious to see how other people do it / what is more common. Your friend is wrong. The advantage/disadvantage +/- 5 is explicitly spelled out for passive checks
Here’s how to determine a character’s total for a passive check:
10 + all modifiers that normally apply to the check
If the character has advantage on the check, add 5. For disadvantage, subtract 5. The game refers to a passive check total as a score.
For example, if a 1st-level character has a Wisdom of 15 and proficiency in Perception, he or she has a passive Wisdom (Perception) score of 14.
The example was passive Perception check. It's not a bad approximation, but it's also a little generous (https://rpg.stackexchange.com/a/81095/22566) because in the case of an actual target being rolled against, the help or harm that adv/disadv will offer will change a little bit with how high the target number is (https://rpg.stackexchange.com/a/14701/22566).

For example a advantage on a 19+ your chance of failure goes from 90% to 81% not quite a +2 bonus on a d20. As compared to +/- 5 that's a significant difference.
Here are the rules from the Free Basic Rules hosted at WoTC's web site, which are what it says in the PHB also.

Advantage and Disadvantage

Sometimes an ability check, attack roll, or saving throw is modified by special situations called advantage and disadvantage. Advantage reflects the positive circumstances surrounding a d20 roll, while disadvantage reflects the opposite. When you have either advantage or disadvantage, you roll a second d20 when you make the roll. Use the higher of the two rolls if you have advantage, and use the lower roll if you have disadvantage. For example, if you have disadvantage and roll a 17 and a 5, you use the 5. If you instead have advantage and roll those numbers, you use the 17. More detailed rules for advantage and disadvantage are presented in chapter 7. If you want to see how the probabilities move about, as compared to a given target number, there are some crunchy things posted here (https://rpg.stackexchange.com/q/14690/22566).

[Demonslayer666]

In my game, I use it the normal way, as stated above. When rolling I use the two dice take the better or worse. When using passive, I use +/-5.

I will grant/impose advantage/disadvantage when there is a clear and distinct reason for it, but it has to be significant (because I also use bonuses and penalties below +/-5).

I also allow advantage and disadvantage to stack to determine if the roll gets influenced, e.g. if you have disadvantage twice, and advantage once, you have disadvantage instead of a normal attack.

[GlenSmash!]

Fortunately Wotc has basic rules that are free for anyone!

http://media.wizards.com/2016/downloads/DND/PlayerBasicRulesV03.pdf

Advantage and Disadvantage are on page 4.

[Ivor_The_Mad]

Oh ok so the -5 is passive. Thanks guys! also thanks for the link GlenSmash!