[h1]Random Encounter Challenge System[/h1]
This system is designed to allow the DM to treat a party's movement through an environment where they might encounter
various monsters as a skill challenge or a set of skill challenges. The goals are to create a fairly simple to run
game mechanic which lets the party make certain strategic decisions and gives each member of the party a chance to
affect the outcome. These challenges are based mainly on the concept of success making the party's job easier, while
failure makes it a bit harder, but overall wandering monsters should have only a modest impact on an adventure as
designed.
[h2]Setup[/h2]
In order to prepare for using this system the DM will need to do a few fairly simple things.
1) Divide up the area in which the party is operating into encounter zones. Each encounter zone represents a region
with distinct wandering monster characteristics. A zone could be a particular area of terrain on an overland map like The Great Southern Desert, or it could be a more specific locale such as The Oasis of Tears, or a very specific setting, like Level 1 of the Temple of Woe.
2) Create a set of encounter statistics for each encounter zone. These statistics will be used in the random encounter
resolution process.
3) Construct a list of possible random encounters for each zone. These can be as simple or as elaborate as the DM
cares to make them and can be either entirely random, used in a fixed order, or selected by the DM as appropriate.
[h2]Encounter Zones[/h2]
Each zone will have certain standard characteristics which are used to resolve random encounters within that zone.
Zone Name - The name of the encounter zone
Encounter Period - Frequency of encounter resolution checks, Daily, hourly, etc.
Difficulty - The difficulty level of the encounter resolution check
Encounter Level - The level offset of the random encounters.
Encounter List or Table - The set of possible random encounters
(see below for an example).
[h2]Party Strategy[/h2]
While traveling through a zone a party can adopt various strategies in order to avoid random encounters.
Each of these strategies corresponds to one of three groups of skills, physical, knowledge, and social which are most valuable while persuing the given strategy. Primary skills for each strategy are those which will produce a success
result if the character makes their skill roll. Secondary skills will produce 1/2 of a success roll. Depending on the
environment the DM may alter these lists. For example in a dungeon type setting Dungeoneering would replace Nature in
most cases. Players can also attempt to use rituals or other similar means to enhance their chances of success. In
general if the use is highly appropriate then it can replace a primary skill and if it may help to a lesser degree it
can replace a secondary skill.
Roundabout(physical) - The party chooses to travel in a roundabout but more physically challenging fashion which will increase the difficulty or time required for the trip but may decrease their likelyhood of meeting wandering monsters.
Primary Skills: Athletics, Endurance
Secondary Skills: Acrobatics, Nature, Heal, Perception
Stealthy(knowledge) - The party simply goes on its way and attempts to keep a low profile by using stealth and general
knowledge to detect and avoid monsters in the area.
Primary Skills: Stealth, Nature, Perception
Secondary Skills: Arcana, Religion, History
Brazen(social) - The party will use bluffs, intimidation, and diplomacy in order to convince any monsters they meet to leave them alone. The party does not make any attempt to avoid monsters and in fact actively announces their presence while making themselves seem as imposing and dangerous as possible.
Primary Skills: Bluff, Diplomacy, Insight, Intimidate
Secondary Skills: Perception, Thievery
Not all strategies may be appropriate to all zones, or some may have
undesirable consequences which are outside the scope of this system to adjudicate. For example roundabout may be
impossible for a party to implement if they can only travel by one specific route, or brazen may be undesirable while
attempting to sneak into a monster lair undetected. The DM should indicate the relative merit of the different strategies
based on the character of the zone. The complexity of the challenge can also be adjusted for different strategies. In
The Great Southern Desert it may be very hard to hide, so stealthy might be a difficult complexity, while roundabout
might be easy since the party can move anywhere in the landscape, and brazen might be medium.
[h2]Resolution[/h2]
During each encounter period the party will declare a strategy which they will use for that period. Then each character
in the party will declare which skill they are using and make a skill roll. The DC of this check is set by reference to
the DIFFICULTY CLASS AND DAMAGE BY LEVEL chart on page 42 of the DMG. If they succeed then either 1 full or 1/2 of
a full success is tallied. If the number of successes exceeds the threshold value for the complexity and size of party
then the party has avoided an encounter. If not then they have failed to avoid an encounter. There are no failure dice
tallied using this system. Each PC either contributes to the success of the check or not.
Code:
RANDOM ENCOUNTER CHECK DIFFICULTY TABLE
PARTY SIZE SUCCESS THRESHOLD
1 1/2
2 1
3-4 2
5-6 3
7-8 4
Note that in general the effect of the difficulty factor will change the chances of a random encounter fairly drastically along the following lines. Easy will result in approximately a 5% chance of an encounter. Medium will
result in approximately a 10% chance of an encounter. Hard will result in approximately a 30% chance of an encounter.
The actual chance for any given party will probably vary by a wide margin depending on how many characters have high
bonuses in an appropriate skill. Assuming that the party will use the most advantageous strategy available and each
character has an available trained skill to check against the above probabilities should be close to the actual values.
[h2]What Was Encountered[/h2]
There are a few ways a DM can use to determine what the party encountered. Different methods may be more or less
appropriate for different settings. Each encounter zone has a Level adjustment associated with it. This can be a handy
way to adjust the atmosphere of different regions, etc. The assumption is generally that the encounter will be level
appropriate to the party. The adjustment can be used to increase or decrease the encounter level relative to the party
level. Thus an area which is very dangerous might have a Level of +2, but a safe area might have a Level of -2. If the
DM uses a fixed list of encounters then most likely this factor is already taken into account, but it can still be
handy to set the level in order to establish the general difficulty of the zone. Some possible ways to generate the
encounter are:
1) List - Use a fixed list of encounters and either present them in the order they appear in the list or choose one
which is appropriate for the situation. Usually once the encounter has been defeated it is crossed off the list.
2) Table - A classic 'wandering monster table' can be used. In this case a set of fairly generic encounters are listed
in a table with die rolls. The simplest system to use for such a table is 2d6. Common encounters go in the middle parts
of the table where they will come up often, unusual ones can come up only on snake eyes or boxcars.
3) Encounter Deck - The encounter deck is described on Page 194 of the DMG. Basically a set of monster cards are drawn
from a deck and the encounter consists of these monsters. The DM can draw monsters until the total XP budget is reached
for whatever level the encounter is.
[h2]Cumulative Consequences[/h2]
As a party wanders around in an encounter zone their actions may have a cumulative effect on their chances of running
into wandering monsters. These cumulative effects can be applied as a bonus or penalty to each character's skill check
in later encounter rolls. For example defeating an encounter will reduce the number of monsters in the area and also
make other monsters less likely to try to hunt down the party. Thus each encounter the party defeats could provide a +1
when the next roll is made, reducing the frequency of encounters. On the other hand if a party flees from an encounter
the opposite might be true and they could be penalized by a -1 to each character's roll. The penalties should not carry
over for more than just the next roll, but bonuses can carry over for as long as the DM wishes. The bonus or penalty
should never grow to be more than +/-2 and should usually be limited to +/-1, otherwise the chance of an encounter will
change drastically.
[h2]Perverse Incentives[/h2]
One of the most likely problems to be encountered with any random encounter system is perverse incentives. In many
situations a party may actually WANT to fail their checks because they percieve that defeating wandering monsters is
a simply way to gain XP and treasure with little risk. In this situation essentially the hunted become the hunters.
The monsters in a given area will pretty quickly come to the conclusion that it is a bad idea to cross paths with the
party and the word will go out, avoid these guys at all costs! The DM can work this system by reversing the bonuses and
penalties under cumulative consequences above in that case. Another solution is the fixed random encounter list. The
zone can simply contain only a certain fixed list of encounters. Once they are defeated they will no longer show up
in the list. The result will be that either the party will exhaust all the available supply of monsters, or they will
defeat all the weak encounters in the list and every wandering monster they meet from then on will be highly
challenging!
[h2]Other Considerations[/h2]
This system is designed to work reasonably well in wilderness type areas. It should also work OK in settings such as a
large dungeon. In urban type settings the consequences of encounters may be more complex, but things should still work
out reasonably well, assuming the encounters are appropriately designed. In such a setting it should be understood that
an encounter means "a significant interaction with the inhabitants." Random encounters also do not HAVE to be in the
form of monsters or NPCs. They could represent discovering an interesting terrain feature or an unusual building in
the city, etc. They can even be used as a sort of random world generation technique.
[h2]Example Encounter Zone[/h2]
Name: The Great Southern Desert
Encounter Check Period: Daily
Difficulty: Easy
Level: +1
Special: The roundabout strategy will result in the party traveling at 2/3 of their normal overland speed and provides
a +1 skill check bonus. The stealthy strategy suffers a -1 skill check penalty but allows the party 10 minutes to prepare for any encounter they have. The brazen strategy operates normally.
Encounter List: Use these encounters in the following order, skipping any which exceed party level + 1. Alternatively adjust the encounter level by adding or deleting a monster.
1) Sand Lizards ...
2) Giant Ant Lion ...
3) Bandits ...
4) Sphinx ...
5) Drakes ...
6) Nomads ...
7) Dust Storm ...
8) Oasis ...
