Roll it back just one second!

[Oofta]

Concerning the multiple rolls, if the target is close to dead, I'll ask them to give me damage one die at a time - even if they rolled everything together. Heck, I encourage people to roll ahead of time before it's even their turn.

Why? Because I want fast-paced action, and sitting there watching someone roll dice and add up numbers is boring. I'd rather have combat be fast and furious, full of a sense of danger, not an opportunity to check facebook while the fighter makes a dozen die rolls one at a time. I trust my players not to cheat. Because honestly unless they're being really egregious or obvious I'm not going to know.

When it comes to assisting or bonuses I prefer that they announce it ahead of time. But occasionally I get "I meant to give inspiration/help". If I think they were just temporarily distracted or weren't following what was going on I'll allow it. I might require a intelligence/wisdom check. That's different than Bob rolling bad and trying to retroactively adding a bonus. I want to promote a cooperative game where people help each other.

As far as assisting things like deception or diplomacy checks, have you never watched a movie/show where a pair of buddies work together to do the flim/flam? Practically every cop show eventually has a good cop/bad cop routine.

To summarize, resolving dice rolls faster is better. Working together is part of the fun. Anything I can do to encourage that just helps the group.

 

[jasper]

Case 1. Yes. I generally will say Ogre below 20, below 10.
Case 2. It depends if the moon is blue, I had a bad week, how the players are acting, how loud is flgs, etc.

PS I HATE THE WORD BLOODED. I only played 4E once. And to keep my monster from the red soda rings of death, see case 1.

 

[Charlaquin]

Nearly the exact situation I originally outlined appears on p.245 of the DMG. Briefly, the DM is supposed to determine whether the aid described is actually helpful, and apply advantage or disadvantage as appropriate. So just as you said.

It's also kind of beside the point, but I'll acknowledge the unintentional red herring. Tom shouldn't have declared he's taking advantage, but then I didn't mean to precipitate a discussion specifically on player and DM agency relating to the help action or working together rule.

I was simply illustrating the premise of a player reacting belatedly to a story being invented moment to moment. It's a question of reconciling the dissonance between PCs existing in adventuring scenarios and players sitting around a table pretending to be those people. I'm curious to examine the still unformed narrative when the die has been cast and the DM is piecing the elements together, when from out of the darkness a player hearkens, "Wait a sec!" in the hope of we haz moar dice!!1

For sure, which is why I followed up with what I would do assuming that I had determined that the second player’s help would have been appropriate to give Advantage to the first player’s roll. Namely, I would allow the player to roll a second time and keep the higher roll, and verbally acknowledge that it was my mistake for not checking if anyone else had an action before resolving the first player’s action. Sorry for setting off that tangent with my initial answer:

To divorce my answer from the specific example scenario and talk a little mor in terms of my general philosophy on these “take-back” moments, I’m of the opinion that it is my responsibility as DM when an action is declared to check with the other players if they have anything to do before proceeding to resolution. When Bob says he wants to scout ahead, I believe it is my job to ask the rest of the table if they have anything they’d like to do before Bob heads off. If I forget to do that and simply ask for Bob’s role, that’s my mistake, and I’m not going to deprive the players of that Bless bonus because of something I did. So I would allow Bob to take that +1d4, or that Advantage, or whatever else, assuming I had forgotten to give the players the opportunity to announce that intention. On the other hand, if I offer them the chance to buff Bob’s character and no one takes me up on it, then no, he can’t benefit from that buff you suddenly remembered you could cast.

I think of it kind of like Priority in Magic: the Gathering. If I cast a spell that lets me draw two cards, I have to pass Priority to you, giving you the opportunity to respond with a Counterspell or whatever, and you have to pass Priority back to me, before my spell is allowed to resolve. If I just tap my Lands, plop the draw spell on the table, and start drawing cards before asking you if you have a response, I’m the one in the wrong. You can call a Judge on me, and depending on the rules enforcement level of the tournament, I can face various penalties. But, assuming this is just a friendly kitchen table game, we might just agree to rewind the game state. I’ll put the two cards back on top of my deck, shuffle my deck if you like, and you can cast your Counterspell. On the other hand, if I do present you the opportunity to respond, and you pass Priority without casting your Counterspell, you don’t get to change your mind after I’ve drawn my two cards.

So I treat actions in D&D similarly. If I ask Bob to make his check before giving the other players “Priority” to cast Bless, or offer aid in some way, you’re in the right to say “wait, I wanted to do X first,” and I’ll honor that. If I asked “does anyone want to do anything to help Bob?” and no one responds, then no, you can’t give him Advantage after seeing that he rolled poorly.

 

[Li Shenron]

In both cases, we're looking at the rapid mechanical resolution of an action before the other player got a chance to announce he wanted to render aid.

I wouldn't let the players get away in any of those example. If you've rolled, you've rolled.

Am I harsh? The point is, if you disallow it the first time it happens, you're setting a rule, so at worst your players might be disappointed once, but they won't make the same mistake a second time and will play along with the established rule. If you allow it, then you're setting yourself up for more of the same ambiguous cases to occur in the future, each time you'll have the burden of the choice. Some cases will lead to trouble, players expecting indulgence, DM ruling otherwise, sour feelings... I think it's better to disappoint once, rather than potentially disappoint more. It's really not that harsh!

Note that this applies to making new decisions after an outcome is determined (i.e. dice results), but it doesn't apply to the case when a player forgot a bonus or an active effect that was already there but genuinely forgotten: this latter case is very different, and I am willing to change the outcome if we haven't gone too far yet. For example: a player missed an attack but forgot advantage > no problem allowing a second roll, but if we've already moved to someone else's turn and backtracking would require to change even more things, then I probably decide it's too late... then again, if someone died because of the mistake, I'll be more forgiving!

 

[Paul Farquhar]

If the DM where feeling generous, one could rule that a skill roll that produces an ongoing effect - sneaking is the only one that comes to mind at the moment - then a rectroactive Guidance might modify the initial skill roll.

Other than that, a task may be repeatable: The player tries to climb the wall, fails, then tries again with Guidance.