I’ve been trying to think of a way to run a journey overland in my game (motivated by picking up Adventures in Middle Earth). I don’t think it’s super interesting to play a normal D&D game out over weeks of travel time (after all: “We keep going in the direction we’ve previously decided to go” seems to cover pretty much everything). We’re introducing a system precisely because we want to have a machine to spit out the results of travel; if we were willing to use the normal adventuring rules, we’d just use those. If the most interesting thing that the system can give us is “you aren’t lost today, and you make your camp in a site which is ambushed that night by 3 black bears. Roll for initiative, you party of twelve level 10 characters”, I don’t think we’ve accomplished much.
These rules assume my long rest houserules; you can’t long rest while roughing it and can only long rest one night in seven anyway. So depletion is a real risk, and it lasts with you until you make it to the end of your journey.
The procedure: Travel is broken down into weeks and days, which are themselves the basic unit of resolution until something goes wrong, at which point the game zooms into an appropriate resolution for what went wrong. Use the usual rules to determine pace, hours marched per day, terrain difficulty and so on.
Each day, the expedition leader makes a Wisdom (survival) check against a DC based on terrain:
- DC 5 (grassland, meadow, farmland)
- DC 10 (artic, desert, hills, open sea with clear skies)
- DC 15 (forest, jungle, swamp, mountains, open sea with overcast skies).
On a success, the group continues on that day, taking appropriate precautions and making good time. On a failure, resolve a Travel Mishaps (see below). And side note: instead of making that check, consider using the Mob Attacks chart (DMG page 250) in order to quickly collapse a number of days down to just the exciting ones. This does mean that a trained ranger can take journeys of fixed lengths without mishap — is that so wrong?
Regardless, each character not proficient in Survival consumes one ration.
First, figure out the weather (DMG page 109). This won’t affect the difficulty of daily travel (that roll includes compensating for the weather), but will affect resolution of the remainder of the travel mishap.
Since weather is based around interesting values being 3/20ths of the total space, we can make a 3d6 roll:
- 1 colder, 2-5 normal, 6 hotter;
- 1-4 no wind, 5 light, 6 strong;
- 1-4 no rain, 5 light rain/snow, 6 heavy rain/snow).
Random things that could go wrong:
|01-25||Delay||1d10 hours of travel wasted on delays, detours, etc|
|26-30||Confusion||Disadvantage on future Wisdom(survival) checks until one is succeeded to navigate; party travels 1d10 hours off course each day until then.|
|31-40||Injury||Pick Strength(athletics) or Dexterity(acrobatics). Each character failing a check against the terrain DC takes 7 (2d6) damage from the travel, but cannot be reduced below 1 hit point as a result of this damage. If it has rained in the last week, the check DC is +5 and the damage is x2.|
|41-50||Disease||Any character drinking foraged water must succeed at a DC 11 constitution saving throw or acquire Filth Fever (DMG p 257). If it has rained in the last week, the disease is Sight Rot instead (DC 15).|
|51-60||Rot||Each character must succeed at a DC 10 intelligence saving throw or else lose 50% of their rations, potions, and scrolls. If it has rained in the last week, the DC is +5 and the damage is 75%.|
|61-70||Ruin||Each character must succeed at a DC 10 intelligence saving throw or else their arms and armor are at -1 (per rust monster). If it has rained in the last week, the DC is +5 and the damage is -2.|
|71-80||Abnormal Weather||Heat wave or cold snap for 1d10 hours. In arctic or desert environments, treat as delay.|
|81-90||Inclement Weather||Precipitation (or heat wave, in desert)||91-99||Storm||Snowstorm, thunderstorm, duststorm|
|00||Powerful storm||Blizzard, hurricane, tornado, downpour (desert)|