In my Out of the Abyss campaign, I moved the characters through 3 phases of Underdark travel which were dependent on their level and abilities.
- Velkenvayle to Sloobdublop – as written. The characters are unfamiliar with the Underdark and have no to little equipment. I rolled for random encounters (ahead of time) and closely tracked food and water.
- Sloobdublop to Blingdenstone (or whatever the next destination is for your party). Use a skill challenge. Characters are more capable. Food is still an issue but not survival so much.
- Blingdenstone to Neverlight Grove/Gracklstugh. Mostly hand waived from this point but with one specific encounter – usually one of the preset ones in the adventure and/or Drow Ambush. Players are higher level, have spells that eliminate the need for food/water and are more adept at navigating the Underdark.
The skill challenge worked well as an in-between option without hand-waving the travel completely. Here is the skill challenge I used. I also have a separate one for travel across the Darklake.
Underdark Travel Skill Challenge
Sloobludop to Blingdenstone Overland
You navigate the hidden tunnels of the Underdark, as you make your way from Blindesnstone all the while trying to avoid the drow hunters pursuing you, the natives and hazards of the Underdark as well as not starve to death.
Complexity: 3 (8 successes before 3 failures), including at least three in total of Perception, Insight, and Constitution.
In addition, the pace of the party affects the DC of the task:
|Slow||-5||Drow Pursuit +1|
|Fast||+5||Drow Pursuit -1|
|Forced||+10||Drow Pursuit reset to 1; any failed check also imposes 1 level of exhaustion.|
Primary Skills: Athletics, Acrobatics, Charisma (Diplomacy, Intimidate, and Persuasion) Insight, Perception, Stealth, Survival, and Constitution. Each primary skill check must be attempted at least once.
Secondary Skills: Aid Another.
Drow Pursuit. If this number ever reaches 5 you are caught by Ilvara and her hunting party from Velkenvayle and must fight to survive. If it reaches 0 you have eluded pursuit for this skill challenge. The counter starts at 1.
Aid Another. You spend your action helping the party in any way you can. The next check has advantage. This action is not counted as a success or failure.
Acrobatics (DC 17). This check allows the group to navigate a precarious ledge or squeeze through a tight tunnel. On a failed check the party encounters a Hazard, and each character loses 1 hit-dice. If the character has no hit-dice to lose then they gain 1 level of exhaustion (you ran out of survival days).
Athletics (DC 15). The drow are strong and single-minded, and the party will have to work hard to keep ahead of their pursers. Helping each other up steep surfaces, crossing precarious rock formations, clinging to giant stalagmites are all potential hazards. On a failed check the party encounters a Hazard, and each character loses 1 hit-dice. If the character has no hit-dice to lose then they gain 1 level of exhaustion (they ran out of survival days). Also, the drow get closer (Drow Pursuit +1)
Diplomacy, Intimidate or Persuasion (DC 17). You encounter a drow warband out on a military mission. They stop you and ask questions – seeming more curious than hostile and clearly in a rush. You need to convince them to let you go your way without raising suspicions. On a failed check Drow Pursuit level increases by 1 and you trigger the Drow Warband Encounter. A failed check maybe cancelled by a successful group Stealth check (Number of N/PCs x 15).
Insight (DC 20) or Survival (DC 15). Underdark caves are vast and seemingly random, but every natural catacomb has an order to it. Characters can make Insight or Survival checks to follow a logical path or guess at a shortcut. On a failed check Drow Pursuit level increases by 1.
Perception (DC 15). The characters are trying to avoid both the drow and the other hostile denizens of the Underdark. A failed Perception check can be negated with a successful Stealth roll. On a failed check Drow Pursuit level increases by 1 and the party must deal with
Constitution (DC 15). The hazards of the Underdark can sap the strength of the hardiest adventurers. Sometimes the best solution is to grit your teeth and struggle through. On a failed check the party encounters a Hazard, and each character loses 1 hit-dice. If the character has no hit-dice to lose then they gain 1 level of exhaustion (they ran out of survival days).
Success: Victory allows the characters to arrive at the outskirts of Blingdenstone while managing to lose their drow pursuers (for now). Additionally, they now know how to safely navigate between Sloobludop and Blingdenstone without having to succeed at a skill challenge.
Failure: If the adventurers obtain 3 failures, they have become lost and run out of food before they get to Blingdenstone. They must deal with a Random Encounter before arriving at the city; they lose 1 hit-die and gain a level of exhaustion.
The adventurers encounter a Hazard at each of the following points in the challenge:
- Each time a character fails an Acrobatics, Athletics, Survival, or Perception check.
- After the party has achieved 4 successes.
- After the party has achieved 8 successes.