D&D 5E [Math/Power] Question for Advantage & Disadvantage

[Syntallah]

A short bit of context:

My PCs were on a small island surrounded by lava, examining a magic circle. For each botched roll, the island sank a few feet, and the lava encroached... muwahahahahahaha. As you might imagine, the pucker factor rose in relation to the island sinking, and the Party Leader started yelling for people to help the sorcerer figure it out. So, I had the priest of Shaundakul [knowledgeable about portals], and the priest with a Sage background [convincing story of appropriate book learning] granting Advantage to the primary PC making the Arcana check.


Now, the problem I have is that Advantage doesn't stack. Even though in my mind, both secondary PCs can lend assistance to the primary, there is no mechanical benefit for such. So the question I have for this august group is this: would it be overpowering from a math sense to let the primary checker roll two extra d20s (one for each assistant), and pick the best of the three?

 

[Nagol]

It skews quite a bit higher, but there is a dread "it depends" attached. If a roll of 1 or more is necessary then advantage doesn't help at all. If a 20 is necessary then the odds go from 5% to ~9.75% with advantage and ~14.25% with double advantage.

What is the base DC required? Here's a chart that compares the base 1d20 with advantaged and double advantaged d20s. Look at the target number and you'll see the expected level of improvement.

http://anydice.com/program/70da

 

[Psikerlord#]

I would suggest still also using smaller modifiers, like +1 or +2, and just use those for "stacking" purposes.

 

[Kobold Stew]

I would not do double-advantage; in fact, I'd suggest that the only help the primary player could receive was advantage from a character who is proficient with arcana. Are either of the helping priests proficient in arcana? If one is, the player gets advantage.

 

[Tony Vargas]

Now, the problem I have is that Advantage doesn't stack. Even though in my mind, both secondary PCs can lend assistance to the primary, there is no mechanical benefit for such.

You could always revert to the d20 semi-generic +2 bonus for helpers after the first.

 

[Pauper]

If the two priests were knowledgeable enough about the subject to assist the sorcerer, they were probably knowledgeable to make their own checks.

In effect, by giving the party multiple rolls, you're giving the entire party Advantage (or double-Advantage) on the check, so if you were willing to let both priests provide Advantage, you may as well just let them roll their own checks (and then let one priest decide whether to make a straight roll or give one of his mates Advantage).

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Pauper

 

[Syntallah]

If the two priests were knowledgeable enough about the subject to assist the sorcerer, they were probably knowledgeable to make their own checks.

In effect, by giving the party multiple rolls, you're giving the entire party Advantage (or double-Advantage) on the check, so if you were willing to let both priests provide Advantage, you may as well just let them roll their own checks (and then let one priest decide whether to make a straight roll or give one of his mates Advantage).

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Pauper

I totally understand what you're saying, but I'm trying to get the players to role-play, and think about problems instead of just throwing dice at it. Too many times around the table, one player will make a check, and the rest will go "oh, I'll roll too"; especially with 5E's 'everybody can try' mentality. This often leads to the guy with little to no proficiency rolling good on a d20 and beating the specialist at his own game. I don't like that.

Friday night was a clear cut example of the guys working together, and I realized that sometimes there's no mechanical benefit due to the no-stacking rule. Thankfully, the players didn't realize it, and the third check was good to go, and it all turned out well. Just got me thinking...

 

[garnuk]

An alternative to providing double advantage is to rule that the DC is lowered by 5. This is reflected in the passive wisdom scores if a character gets advantage to perception checks.

 

[Pauper]

I totally understand what you're saying, but I'm trying to get the players to role-play, and think about problems instead of just throwing dice at it. Too many times around the table, one player will make a check, and the rest will go "oh, I'll roll too"; especially with 5E's 'everybody can try' mentality. This often leads to the guy with little to no proficiency rolling good on a d20 and beating the specialist at his own game. I don't like that.

I see your point, and I agree -- the idea that everybody will just automatically pick up a die and expect that someone will roll high to fix whatever problem the party is encountering is a pretty disappointing development for a role-playing game.

With that said, you're the guy who presented the party with a challenge that effectively would end the adventure if one guy couldn't roll well that night. If you're really trying to encourage RP and thinking about problems, consider giving an automatic success if the arcanist actually described a solution that should work, especially if it involves expending resources like spell slots or consumable magic items. Otherwise, 'thinking about problems' doesn't become an end in itself; it's just another way for the party to max their die rolls.

--
Pauper

 

[jgsugden]

It depends on the roll required for success. If you need a 5, then the difference between 2d20 and 3d20 is not that significant - you'll get it almost all the time anyways (fail on 1 in 16). If you need a 19, then you're adding a significant amount to the chances of success .... and if you're talking attack rolls with a chance to crit, then the added die is also increasing crit chances and that has a huge impact...

I recommend just using the rules as written: They work, although you sometimes need to figure out the best way to apply them.

With regards to knowledge rolls, I usually have one PC make the roll and let other PCs help. That gives them one attempt - and advantage on the roll. However, I do not let someone help unless they have a reasonable basis to be able to contribute. For example, a barbarian with Int 8 and no Int based skills that wants to help a wizard/rogue with a +16 to Arcane checks perform a DC30 arcana check is not going to be able to help. However, if the wizard's arcane roll is to figure out an ancient magical puzzle, the fighter with a sage background and proficiency in history might be able to drum up some historical fact of use - and can offer his help.

Too many rolls destoys role playing. Too few mean that there is no chance of failure. 1 attempt with advantage gives you a nice window to control a reasonable chance to succeed while maintaining a chance of failure. It is a nice balance.