In Out of the Abyss, PCs are equipmentless and travelling in a dangerous and hostile environment where food and water is scarce. To top it all off, they are actively being hunted down by an overwhelming force. The PCs are out of their element, lost and hungry and with no means to magically "cheat", being at a very low level to have access to useful magic. They also have almost a dozen other mouths (NPCs) to feed.
Our party composition is: Inquisitive Rogue 3 (from the UA), War Cleric 3, Old One Warlock 3, Vengeance Paladin 3. There are also 7 NPCs that managed to stay alive (3 died in the first session). Apart from the Dwarf Scout that is with the party, highest survival in the party is +4 (the Cleric) or +3 (the Rogue). So food is a very big issue during the journey.
I like how the module forces the PCs to be on their toes with logistics, requiring Wisdom (Survival) checks to find enough food and water to survive. And we enjoyed RPing who got enough food and dividing it up among the party.
What I don't like is that the PCs are making the check every day of travel. It was fine for short travel (a week or so, 7 checks, no big deal) but over really long distances of almost a month of travel, it quickly became not fun to roll 28 times and adjudicate who gets to not eat on a particular day.
Is there an alternative that doesn't ignore the urgency of finding basic needs like food and water?
Though related, this question asks mostly about rolling a large number of dice, like twenty d6s. However, foraging is much more complex — it involves a single PC rolling a Wisdom (Survival) check against a certain DC then if it succeeds, the PC finds a number of pounds of food equal to 1d6+WIS.
Best Answer
Cheese as a Food Group that can Help
(TL;DR You don't need to roll every day if the party uses this approach, but on the real tough days (DC's > 15), there will be some rolls that reflect how Out of the Abyss is a hard adventure).
Get Help when Foraging
This approach may smell of rules manipulation, and will only work if you accept this as the DM. The party and NPC's together can create advantage on all of the foraging efforts by using the Help rules for ability checks. As you do not define a DC I'll offer three examples when I sum up.
Rule of Thumb: Advantage amounts to a +5 on a given ability check.
As the DM, you first need to determine the following: since it's a survival situation, is there a valid reason that the NPC's will not help foraging? It's their necks too if they all starve. If there is a reason that the NPC's can't or won't forage, then what follows is at best partly applicable, and possibly inapplicable.
Working Together
This works for foraging. Why?
- Searching for food is something you can do alone.
- Two people looking for fungus/fish/bugs/caviar/water have a better chance of at least one of them spotting food/potential food and water.
This matters because once a player character has exhaustion, that player gets disadvantage on further ability checks, which cancels out the advantage (+5) bonus of help. On the other hand, once enough characters have a level of exhaustion, help (advantage) can reduce the effect of disadvantage on skill checks (foraging/survival). In this regard, after some bad luck days or a few days of DC's at or near 20, not having disadvantage can mean the difference between success and starvation.
Exhaustion (p. 106 Basic Rules)
\begin{array}{r|ccc} \text{Level} & \text{Effect}\\ \hline \text{1} & \text{Disadvantage on ability checks} \\ \text{2} & \text{Speed halved} \\ \text{3} & \text{Disadvantage on attack rolls and saving throws} \\ \end{array} Once the foragers lose advantage due to exhaustion, the risk of a vicious circle of failed foraging looms. Foraging is a priority concern for this phase of the adventure.
As in RL, water is the more critical resource to avoid exhaustion. The gathering rate for a successful foraging check (water) is 1d6 + wisdom gallons. (DMG p. 111).
Water Requirement: One gallon of water per day (Underdark, we'll assume that it isn't hot enough to trigger double requirement).
Half water rations forces a DC 15 Constitution saving throw of one level of exhaustion, added at the end of the day. Less than half rations automatically adds another level of exhaustion at the end of the day. If the character already has one or more levels of exhaustion, the character adds two levels of exhaustion. Lack of water triggers a compounding exhaustion problem, with the ability to forage impaired at only one level. Thirst kills.
Needed resources:
4 PC and 7 NPC ~ 11 gallons of water per day.
4 PC and 7 NPC ~ 11 pounds of food per day, with an occasional half rations day being acceptable.
Foraging rate: on a successful check 1d6 (+ wisdom bonus) pounds of food.
The objective: enough food and water to avoid exhaustion levels that harm the party.
Foraging and Difficulty
Top foragers:
Cleric has +2 Wisdom Bonus (per your data)
Rogue has a +1 Wisdom bonus (per your data)
Foraging check prospects DC 10:
With advantage (Help) cleric's the modifier amounts to +5. His +4 means even on a rolled 1, he finds food. Average of 5.5 pounds of food per day. (1d6 + 2)
Rogue with a +3 and the +5 help has to roll a 1 to fail: 95% chance to succeed with help. Yields an average of 4.5 pounds of food per day.
Average take: 5.5 + .95*4.5 + .8*3.5 + .8*3.5+ = 15.375 (15 3/8) pounds of food per day when using help. The prospects are very good, particularly if they over forage now and again to have enough for half rations for the day that everyone fails.
Bottom line: when the DC is 10, food isn't a problem if they use Help with foraging. They can store food for harder days.
Foraging Prospects for DC 15:
Cleric with Help is +9: a five or less fails. .75*5.5 average = 3.75
Rogue with Help is +8 so a six or less fails. .70*4.5 average = 3.15
Warlock with Help has +5 so a 9 or less fails. .55*3.5 average = 1.925
Paladin with Help has +5 so a 9 or less fails. .55*3.5 average = 1.925 lbs
At an average of 10.75 pounds per day, the party needs someone to go half rations most days, or get maybe the Dwarf Scout to forage as well with help.
Foraging Prospects for DC 20:
Cleric with Help is +9: a ten or less fails. .50*5.5 average = 2.75
Rogue with Help is +8: an 11 or less fails. .45*4.5 average = 2.025
Warlock with Help has +5: a 14 or less fails. .30*3.5 average = 1.05
Paladin with Help has +5: a 9 or less fails. .30*3.5 average = 1.05
At an average of 6.825 pounds per day, the party needs someone to go half rations most days, the Dwarf Scout ought to forage as well with Help (another 1.05 pounds from that pair), and maybe have another pair of NPC's do likewise. When the DC is 20, or high like that, getting that food is what makes possible getting the following day's food.
Resource issue: at the cost of a precious spell resource, the Cleric can create water (10 gallons, Create Water 1st level spell) if there is no water to be found. Because of how critical water is, see the compounding exhaustion point above, that may be a reason to save one spell slot on the really hard days to make sure nobody gets disadvantage the following day for the search.
The above shows how well they do when party members forage with an NPC performing the "help" function to assist with the ability check. While the Rogue and the Cleric are likely to get the most benefit since their Survival checks are highest, all of the character/NPC pairs can roll with advantage. This means that most of the time, they can forage enough unless you trigger conditions that prevent it. When DC's get very high, things get dicey, so that is when the rolls need to be made.
How does this answer your question?
Mostly, it means that if the party can concentrate on foraging and DC's stay 10-15, they can keep going. No need to roll (see the average foraging rates using Help) since they'll average enough food per day. That means that you only have them check when it is significant, or when a significant change of condition occurs:
You can control how successful the party members are in foraging by adding or subtracting other encounters/things that occupy their attention so that on some days, all of them can't forage.
Adjust the DC to any value you like, run the template again (when the terrain or conditions change significantly) and see how likely failure is. Then the fun part comes: the role playing interactions on who goes on half rations, who doesn't, and why? (Hint: keep the Cleric and Rogue fed! They are the party's seed corn). It's up to the party to play out the food distribution, with your input from the hungry NPC's.
Or, you can ignore all of that (if you feel that it's an exploit, and that this Underdark scenario in Out of the Abyss is trying to stress the characters in a survival situation) and not let Help operate in that manner. You're the DM, it's your ruling to make. What the above provides is a method within the rules that leaves you open to picking your spots where you make foraging matter and thus force a foraging roll since success or failure becomes significant on certain occasions.
FWIW, @BenBarden points out that if one gets down in the numbers, the +5 is a sweet spot for advantage rolls. If you go through the details at the link, you can see how the bonus for advantage will vary as the difficulty / DC / Target Number varies. You may want to adjust that "+5" - but the whole point of advantage and disadvantage a s a mechanic is to replace the fiddly bits of stacking plusses and minuses that we all know and love from previous editions. A good reason to consider just going with the +5 is on page 62 of the Basic Rules, the straight "+/5 for adv/disadv" is used for passive checks.