Traveling the Underdark

Traveling through the Underdark is a dangerous proposition, not undertaken lightly. Trade is rarer than in the lands of light, and usually facilitated by imposing guardians who travel with caravans.

Travel Pace

The pace that a group travels at largely determines what they are capable of doing as they travel. Only smaller, mobile groups are able to travel at Fast. Any more than twenty individuals or groups with wheeled vehicles are limited to Normal and Slow pace.

Pace	Miles/Hour	Effects
Fast	1	Navigation, Perception, and Tracking at disadvantage Foraging, Mapping, and Stealth impossible
Normal	.75	–
Slow	.5	Foraging, Navigation, Perception, and Tracking at advantage may use group Stealth

Traveling Tasks

• Forager: The forager hunts for the signs of food and water while traveling through the Underdark. Foragers are also usually involved in hunting for a good spot to make camp in towards the end of a day's march.
• Mapper: With the right tools, a mapper can produce a map of the route the group travels. While this doesn't aid their current travel, it provides them with a useful resource for retracing the route. Good maps can even be sold in Underdark settlements by enterprising cartographers. This is a daily DC 12 Intelligence check to do successfully, though proficiency in cartographer's tools obviates the need for a check. A failed check renders the map useless.
• Navigator: The navigator handles the route through the Underdark, making sure they stay on course. A navigator generally needs at least one of three things to successfully navigate the Underdark: familiarity with the route, maps or charts, and a set of navigator's tools.
• Tracker: A tracker is used when the party is following a trail or set of tracks. This is generally a daily DC, with an additional check necessary after encounters.
  • A group may also employ a "counter-tracker" while they travel, having someone take the task of covering and concealing their tracks. This person must be in the back ranks of the marching order, and must make a Wisdom (Survival) test. This result becomes the DC for anyone attempting to track them. Performing this task while moving Fast is at disadvantage; moving at Slow pace grants advantage instead.
• Others: Anyone not performing one of the above tasks is assumed to be keeping an eye out for trouble, applying their passive Perception to their surroundings. Some threats may only be spotted by those in specific parts of the marching order, generally the Front or Rear.

Foraging

• For each day of foraging, a character may make a Wisdom (Survival) check, with a DC based on the environs.
• Success on the check allows a single roll on the Foraging Table, which is a d20 roll.
  • For each 5 full points above the DC, the foraging character may make another check on the Foraging Table.
• Multiple characters may make foraging checks during travel.

Mapping

• During days of travel, the mapper is assumed to be recording the paths the group travels through.
• If the mapper has proficiency with cartographer's tools, this happens automatically, as long as they have the tool kit.
• If the mapper does not, they must make a daily DC 12 Intelligence test. Success provides a normal map; a failure should be recorded. Upon accruing three failures on this test, a map is too flawed to be successfully used for navigation.
• Copying Maps: Copying a map takes one hour per day of the route In question.
  • Someone proficient with cartographer's tools can make an Intelligence (cartographer's tools) test, DC 14 to reduce this time in half.

Selling Maps

• Finding Buyers: Cartographers, merchants, pilgrims, and even folk needing to travel from one place to another may all have cause to purchase a map.
  • It takes a day's effort and a DC 14 Charisma check to find buyers. This DC increases by +3 for every additional day of searching for purchasers.
  • Success results in finding 1d4 + Charisma modifier number of interested buyers.
  • Failure indicates there is no further interest in the map specifically.
• Price: The base price of a map is a number of gold pieces equal to the number of days on the route. This may be multiplied by 2 for routes through wild areas, 5 for routes through particularly dangerous or untraveled areas, and by .5 for maps of routes through well-traveled areas.
  • Haggling for the sale of that map is handled through normal haggling rules.

Navigating

There are three elements that make navigation possible in the Underdark. Having at least one allows the character to make a Navigation check at disadvantage. Two permits a normal check, and three grants checks at advantage.

• Familiarity: A character familiar with an area can be of tremendous benefit towards getting around in it. Moreover, this person doesn't have to be the navigator, although their traveling task does become aiding the navigator.
• Maps: A good set of maps for Underdark travel generally covers routes rather than broad swathes of terrain.
• Navigator's Tools: Though a normal set of navigator's tools is insufficient for delving through the Underdark wildernesses, most settled areas of the Underdark do sell navigator's tools for Underdark travel. Using it is the same proficiency as navigator's tools.

Navigation Checks

• A Navigation check is made when a group starts traveling again after each long rest, short rest, or encounter.
• The check itself is a Wisdom (Survival) test.
• The DC for this test is based on the area in question.

Navigation Results

• Success on this check results in travel through the area without getting lost.
  • Achieving a result 5+ higher than the DC allows passage through a route that "eats up" an additional 1d4 hours from the time to reach the destination.
• Failure on this test results in the party getting lost.
  • Lost characters wander through the tunnels, caverns, and byways of their location for 1d4 hours.
  • At the end of this time, the Navigator of the party may make another Navigation check.
  • Three failed checks in a row results in the party ending up in a location that none of them are familiar with, and that is off of any of their maps.

Setting Camp

• Towards the end of a day's march, travelers usually begin hunting about for a decent camp site. An ideal site has a number of good traits: a source of fuel for a fire, relative dryness, flat surfaces for sleeping on, limited approaches to the site, and a site that is tucked away out of general sight. Some may also have natural resources, such as water, food, herbs that aid in healing,
• Finding a camp takes an hour of travel, and is a Wisdom (Survival) test, at a DC based on the terrain.
  • If the group has more than one forager, use the best bonus, at advantage.

Results

Success results in a spot that has three of the following traits. For every 3 points above the DC scored in the test, add one more trait. Failure indicates no site with any of these traits can be found.

• Fuel Source: Mushrooms and thick lichens grow nearby, with sufficient density to build and maintain a fire.
  • The patch can provide fire for 1d6 days before being exhausted.
  • A site without this trait cannot have a fire (which is necessary for recovering from cold-based exhaustion, Damp, or preparing food gained by hunting animals).
  • Otherwise, the group must bring their own fuel with which to build fires overnight.
  • The site's fuel can be harvested during the long rest by one individual, acquiring fuel that weighs 3lb per day's worth of fuel.
• Dry Site: The site is dry enough to sleep and store gear at without danger of water damage or mildew.
  • A site without dryness accumulates 1d4 points of Damp. Some areas (those close to large bodies of water, for example) may generate higher dice values of Damp.
  • Add the Damp rating cumulatively to a group's gear. At the end of each day's travel's everyone should make a check of 1d20 + current Damp rating. An 18+ results in losing 1d6 items to the creeping, insidious wet (a single person-day of food counts as 1 item for these purposes).
  • A long rest spent with a camp fire eliminates 2d6 Damp from the group's gear.
  • Trying to sleep in a damp area requires either a Constitution or Wisdom save, DC 12 + Damp generated. Failure on this check means the character gets no benefit from that long rest. This check is made at advantage if the character sleeps in a tent or similar shelter.
  • Finally, characters resting and traveling with active Damp may become ill.
    • At the end of every day's travel while the group has a Damp rating, everyone must make a DC 8 + total Damp Constitution save.
    • Failure results in illness. This illness immediately strips a hit die from the victim, which cannot be regained until the illness is defeated. This save is made every day, losing more and more hit dice as it progresses.
    • An application of lesser restoration can cure it, as can a long rest spent with food beside a fire. As long as
• Sleeping Surfaces: The site has sufficient flat space for everyone to stretch out in while they rest.
  • Lacking this forces a DC 13 Constitution or Wisdom save, attempting to sleep at odd angles, with sharp protrusions in the body, or in absurdly cramped space. Failure on this save means the character gets no benefit from that long rest. Characters with bedrolls may make this check at advantage.
• Limited Approaches: The location is not out in an open area; there are only 1d3 ways of approaching the site. Sites without this feature are open on most sides, and are vulnerable to attack from many sides.
  • A campsite with this feature grants advantage to the Wisdom (Perception) of those who are keeping an eye out for the approach of enemies.
• Sequestered: The camp site is difficult to notice for creatures passing by. Creatures that encounter it do not automatically detect the site; it is a DC of 10 + 1d6 to do so. If the site has a fire or lights lit, the passive Perception receives advantage.
• Water Source: There is a source of water nearby.
  • There is a 30% chance that it is a flowing, renewing water source like a spring, stream, or well, providing as much water as the party wishes to consume and carry away.
  • Otherwise, it is a more limited accumulation, in the form of drip pools, condensation wells, steam caches, or water orbs. It provides an opportunity to make a single Foraging test, providing water only.
• Food Source: There is a source of nourishment nearby.
  • There is a 40% chance it is animal-based; otherwise, it is plant-based.
  • As part of the long rest, someone may harvest this resource, making an additional Foraging test, providing food only.
  • Only one person may make this test, as it is a limited supply.
• Herbs: Medicinal herbs or mosses grow nearby. The fresh herbs may be used to make Medicine checks at advantage while on the site.
  • A character with proficiency with herbalism kit may harvest and preserve the herbs to generate 2d6 "refills" for healer's kits in the party. This isn't enough to make a healer's kit from scratch, just to renew expended uses of existing kits.

Tracking

• Tracking is a Wisdom (Survival) check, with a DC based on the age and overtness of the tracks and the terrain in question, or on a DC equal to the results of the opposed Wisdom (Survival) check used to hide tracks.
• This check must be made at the end of every rest (long and short), as well as after every encounter.

Watching

• Every character not performing some other function is assumed to be keeping an eye out in the environs as they travel. This allows them to apply their passive Perception to possibly notice traps, hazards, and encounters.
• Characters performing tasks have a chance of noticing things, although it is greatly reduced: apply disadvantage to their passive Perception.