Them Bones of Adventure - XXIII: Underworld Delving Encounters

An ongoing exposition on table procedures for common exploration feats and rules, which began here with part one.

Introduction

As both mine own thoughts as well as those of the gestalt have been steadily coming back to dungeon exploration and random encounters I figured I’d belabour the thinking presented in this post so as to tie into a greater procedural structure.

Random encounters can be held to serve a vital function as exploration timer, the “stick” part of an equation, to treasure’s “carrot”. Much as I appreciate their unpredictability and the emergent gameplay they offer I still did wish they had some better integration into the play experience, getting more out of them as a feature that added to the game as a source of decision points rather than just an immutable fact of life for the would-be delver.

I can understand why a cynic would dismiss them as a cheap thrill of dungeoneering: they usually carry little weight, amounting to piddling setbacks or speedbumps with HD; to be allowed to be more than nuisances, their nature and terms of engagement must be better defined, lest they cause a party to perish whimsically. As there is only so much structure to which one can bind a procedure before it starts feeling helplessly artificial, ultimately, this randomness will tip the scales onto the “game” side of the balance rather than serving a narrative purpose, as some crude pieces of game-wiring must by necessity be exposed and loudly twanged each and every time. It is up for the canny referee to then provide enough oxygen to fan the flames of emergent narrative rather than settling for cold algorithm.

Grounds Fit for Spawning

The use of a random encounter table and associated encounter chance presumes a place at once big enough and with enough creature activity to be assigned a periodic roll during a delve. Small complexes are better served by having either a simple adversary roster (with keyed initial positions, subject to change) or even simpler “present/absent from lair” percentual toggles for keyed room contents.

Past the assumption of an underground sprawl sufficient to propitiate the use of this kind of procedure, even the act of relying upon it can be tailored to transmit a mood and tone and be made gameable by dint of allowing the actions of a party to either exacerbate or mitigate the chances of encountering the sources of fruitless, potentially deadly attrition contained therein.

Most if not all published modules suffer from an excess of unlikely neighbourhoods and untenable stati quo encounters in near-adjacent chambers, stretching believability past even the fantastical. It bears the question of whether the brunt of the load should be shouldered by random encounters, while leaving the keyed material for setpieces, inanimated background dressing and terrain features.

The gist of my current thinking on this:

.: The roll for chance of encounter should be made public and be sensibly influenceable by actions taken by the party; This should not be seen as breaking the fourth wall since the occurrence of an encounter indicates precisely that the party has become aware that something is off.

.: Modifiers to the roll should be avoided, with preference given to different sized dice so as to keep the result as quick to assess and transparent as possible, given that it’ll be oftentimes repeated.

.: The encounter roll proper should be separate from any subsequent rolls for determining encounter specifics, which by necessity must be kept hidden, for despite the fact that the party is aware that something is close by means not at all that the characters will know what it is or where it lies.

On Stealthful Exploration

Minimizing the number of irrelevant choices becomes important when winnowing game mechanics down to a simplified core. One such false idol for the beleagered delver party is the declaration of silence: whatever its members may happen to be doing from moment to moment, from checking for traps to searching a room, it must be presumed that it is being done at the very lowest volume the activity will condone. The PHB makes a show of tripartite scaled movement, but the question is: does anyone run such a tightly wound joint that halving the movement rate of a cautious party as it explores excavated halls measured in tens of feet and saying it takes a minute longer to cross a room mean anything at all? I very much doubt it.

While a party moving overland can validly declare to be moving cautiously as this carries the impact of a cost in ground covered, as less distance travelled over the course of hours does accrue and translate into more days spent in the outdoors and more provisions spent, those cavorting about the corridors of daedalus, their motions defined by halting progress, faltering stops for listening around and nervous turning of corners have quite no such choice: moving discreetly is not so much an option as it is the norm, one for which a referee ought to require signed declaration if the party ever states to be breaking.

As such, there are only two recognized movement modes down in the underworld: cautious (the gold standard) and heedless (when on the run from someone or something). To get a better deal out of it, tangible measures have to be taken by the players, ones with attached tradeoffs, rather than just wrily stating that “the party takes it slow”.

The Crunch

The Encounter Roll

Transfering random encounters across the threshold of nuisance into that of serious deterrent means that many of the preconditions and outcomes inherent to the procedure should be clearly communicated to the players, even if then varnished with prose.

As a way to paint undertones of urgency, the random encounter roll is made out in the open, the referee explaining what die is being used and the reasons why. Past that, there is arguably a need for veiling the results derived from the procedure, insomuch as the consequences won't always be fully apprehendable by the characters, with whatever fragmentary information eventually pieced together functioning as exploration of a sort, as the players begin decyphering a dungeon’s internal logic.

Despite liking enriched die rolls the advice goes against resorting to this check’s result to tell if characters are tired, hungry, light deprived or otherwise cut short the duration of spells or other effects, limiting it instead to strictly unpredictable effects such as spoor, dungeon-related events (still allowing for the classic gust of wind that snuffs light sources) and, of course, the encounter itself.

“Fool of a Took!” – When to Check

A dungeon encounter is checked on the following conditions:

- For every 10, 30 or 60 minutes of in-game delving elapsed, depending on the scale, population density and activity level of an underground complex.

Despite 10 minutes being standard, for the sake of injecting some dynamism in an environment, there may be places where a check is called every 60 minutes so as to represent fallow slices of the underworld (such as the Mines of Moria), these time intervals then becoming reduced as the disruptions borne by events begin to pile up and the anthill comes alive with activity. Normalizing then requiring a number of successive checks without returning any encounters or a number of hours of stillness.

The above timings are either worn down by the duration of prolonged tasks such as searches or, for the case of time spent on nothing but trifling actions and simple cautious movement, abstracted to a rough basis of “d6 rooms explored per every 10 minutes” or, if covering ground already mapped before, “2d6 rooms entered per every 10 minutes”, rolled and counted down in secret by the referee.

Past the point of entering the last room in the countdown, the rolled total can then double as the number of player declarations taken by the referee before the encounter is suddenly rolled for. This extra granularity is meant to deliberately disrupt exploration mid-point, broadening the range of possible individual character positionings rather than always declaring the encounter roll once the party inches past the threshold of the last allotted room and then relying on the staid default formation.

- Whenever noise or commotion is made, including combat (one roll per every minute – 10 rounds – of combat) or rushed movement (one roll per d6 rooms traversed).

Chance of Encounter

- A roll of 4+ means nothing happens;

- A roll of 3 can either be reserved to trigger dungeon-specific conditions as needed but by default also returns an empty result;

- On a roll of 2 the party finds tracks, spoor or other traces of recent activity (unlocking the possibility of tracking, if the traces are recent);

- On a roll of 1, an encounter comes across the party, their efforts at stealth nonwithstanding;

This is a standard result mapping, of which some results can only happen if the party is moving about. The chance of encounter can also be increased by specific hostile actions or events, such as the party being actively searched for (e.g. if they’ve allowed an alarm to be sounded).

Encounter Die Size

- The standard die size of the encounter check is dictated by the environment, varying with each dungeon level or location. It is meant to account for a five-element group moving cautious and silently, bearing one significant light source. From here, it can get better or worse, depending on the group’s composition and measures taken by the party:

Encounter die size decreases (increasing the chance of an encounter):

- For every two additional characters in the group

- For every two characters donning heavy armour or heavily encumbered

- Per significant light source beyond the first

- If the party hastens or otherwise forgoes its cautious movement

Encounter die size increases (lowering the chance of an encounter):

- For every two less characters in the delving party

- If the delving party does not move (also cancelling out any encumbrance and armour penalties gained above)

- If a significant light source is extinguished

- When the party hides (quality of hiding place determining the die size)

Thus, if a group of five delvers burdened with treasure is looking at crossing an expanse of dungeon boasting a standard encounter chance of d8, tested once every 10 minutes, the players will know that choosing to press on in their present condition is bound to bring attention to their doorstep on a 1 in 4, whereas they can lie still as they rest for an hour with an adjusted range of a 1 in 10 chance of being found, heard or tracked. This could be further improved to a 1 in d12 by the choice to douse their sole light and rely on the dwarf’s sight instead (with a light spell at the ready), though this would severely limit what actions the characters could take and with potentially grievous consequences should an encounter actually occur.

- Just as a dungeon has a standard encounter die size, so it will have a minimum size of d4 as well as a maximum size cap, usually d20, though this can rise further for labyrinths spanning leagues or when the party absconds into a particularly effective hiding place.

- If a party splits past a significant distance, meaning far enough apart to have darkness and unguarded passageways between the delvers, separate encounter rolls will be merited for each splinter group.

Dying of the Light – Interactions between Light and Encounter Mechanics

Being thrust into the dark is unnerving. So is trying to make light interact meaningfully with random encounters in a way that doesn’t just spell “the less of it, the better”.

Some creatures will be indifferent to light, others will shirk from it, others still will rely upon it just as much as the characters. This is not about them. Although the encounter abstraction factors in the possibility for the party to intuit the presence of others from either vestiges or sounds, their sensorial handicap will pretty much ensure that underground denizens cannot fail to notice an overlander party first, shining like a beacon. Yet, despite the use of one or more sources of illumination being a surefire way to increase a group’s chance of detection by hostiles, there are tradeoffs to consider:

- Characters need light to function in the underworld, a referee wanting to emphasize this fact might contemplate always questioning the light bearer first as to any actions or movement taken, the rest of the group then having to follow the lead when accounting for their respective actions.

- The extent of bright light radius covering the lead character (relative to an encounter’s approach) will determine the minimum encounter distance, guarding against hostile stealth attempts that cannot cut through to a target enveloped in a pool of bright light.

- Each significant light source beyond the first adds 5’ of bright light and 5’ of dim light to other sources overlapped by its radius. This may seem of little consequence but could well be the difference that allows the party to get to grips with foes that would otherwise wear the characters down from beyond the reach of their senses.

Party Formation & Marching Order

Overshadowing the tactical reasons, a notional positioning of each character relative to the other atoms of the group is necessary to provide a default answer to reiterated uses of the encounter procedure, dispensing with the need for each player to exhaustively restate where their character stands each and every time a check is triggered, leaving at most a limited range of positions as the formation expands or contracts to suit the terrain or the size of the room. This standard arrangement being overriden, of course, whenever explicit placements are stated by players.

Mutual Appreciation Society – Encounter Distance

Whenever an encounter occurs, the encounter distance roll itself serves to establish when (and, rarely, if) each party becomes aware of the other. This is a situationally fluid topic: for medium distances, it is assumed both groups have become at least dimly aware of each other; for short distances it is assumed that the encounter has slipped by unnoticed until now as it has the drop on the PCs, whom it has actively ambushed or around whose vicinity it has been skulking for some time; finally, for long distances it becomes a possibility that the party has become aware of the encounter but the opposite hasn’t yet happened.

The roll for determining the Encounter Distance from the contacting character is made in secret and framed by two fundamental factors:

- A minimum distance equalling that character’s coverage by the bright light radius, if not blocked by obstacles or interposing cover.

- A standard maximum distance of 2d6 x 10’, increasing the dice size for encounters with large-plus creatures and for every six medium-sized creatures (or whatever other factors that may prove relevant).

Skill Interactions with Encounter Distance

As regards skills, where some might find this a situation made for flexing the stat blocks of the parties involved, this approach leans instead towards simplicity:

- Perception: If the character who is the point of contact has ranks in Perception, add a roll of his proficiency die to the encounter distance.

- Stealth: If the encounter is deemed to be making a stealthy approach the referee makes a roll of the highest Stealth proficiency die common to the whole group and subtracts it from the encounter distance (for the sake of simplicity it is assumed that only groups of creatures wholly proficient in stealth would manage to engage in a cohese approach relying on it).

The Encounter’s Path of Approach – Biasing the Encounter Distance & Determining Point of Contact

- Firstly determine from which directions the encounter might conceivably come from. This must account for the labyrinth’s topography, creatures’ special movement modes if any and the party’s present location (of which the referee should keep tabs through the use of a dungeon blueprint of some sort). Encounters will typically originate from unexplored directions but parties who don’t (or can’t) secure their rearguard can run afoul of all manner of unwanted surprises.

- As the distance dice pool is rolled, trace an imaginary line between its highest and lowest result, adjusting and translating this to the closest point in the actual topography and informing the players as to the encounter’s path of approach, even if it is not yet visible, the characters having intuited its direction through sound, air displacement, smell or other factors.

- If a double is rolled (or other unclear result), it means the party becomes aware of the encounter but is unable to pinpoint its path of approach: if it is not yet visible, the referee randomizes its approach some other way but does not disclose to the party where the encounter is coming from.

In any event, determining an encounter’s bearing will provide a biasing point to enable the distance rolled to make sense:

- The character standing closest to the encounter’s path of approach becomes the point of contact from which the encounter distance is then biased, being the one who detects it first.

Going for the simplest example, if a party is wholly inside a room with a single door (a cul-de-sac) when an encounter is rolled this’ll mean the referee determines its distance relative to the character standing closest to the doorway and the direction of approach as conforming to the immediate surroundings of the chamber’s sole point of entry. Rooms or hallways with more complex connections will allow for a greater range of possibilities, assuming the party doesn’t actively take steps to minimize possible angles of approach.

Contact – Close Encounters of the 3d6th Kind

Finally, depending on the encounter’s rolled distance, path of approach and skill interactions one of five situations will typically present themselves:

For long distances (180’ and above)

1. Distant Sighting: Party has become aware of the encounter without being noticed in turn;

For medium distances (40’-170’)

2. Imminent Contact: The distance roll places the encounter beyond a door or tunnel bend from where it is heard approaching, affording the party a window of opportunity: the players get one combat round to act plus another granted for each distance die that came up a 4+ before the encounter materializes. Note that movement beyond half speed will result in the party’s stealth becoming immediately compromised;

3. Avoiding the Light: The encounter lies in sight of the party but has shirked the group’s light radius, meaning both parties are aware of each other but whichever decision the players take will have to be made without knowledge of the other side’s exact nature, position or intentions;

4. Standard Encounter: The encounter occurs within the light range meaning that the two parties become mutually aware as one steps through the other’s visual threshold, unfolding normally;

For close distances (0’-30’)

5. Ambush!: The party has been waylaid, ambushed or suddenly become aware of a lurking threat: the encounter has initiative and the party will need to roll for surprise;

These are merely guidelines, not an airtight behavioral algorithm meant to overcome all logic. It is certainly possible to conceive of encounter types who would rather keep a safe distance and are instead thrust by a low roll right into the clutches of a numerous melee party, it being up to the referee to reconceptualize such occurrences as they appear (e.g. the lone goblinoid wasn’t looking to attack but is instead a skirmisher or would-be thief, drawn by food or curiosity). Likewise, if the party gets a glimpse of an encounter that lies at an inacessible spot tentative communication or missile exchanges may be possible but a full-fledged interaction is unlikely to occur;

While underground, all of the above works from the assumption that the party is carrying a light source and whatever denizens encountered are not. If an encounter itself is carrying a light source, recognition is much more immediate, with situations “3.” and “5.” becoming moot.

Hammers and Anvils – Mastering the Dungeon Environment (Closing Thoughts)

It would be admittedly easier to downtune the complexity instead of mucking about with encounter approach vectors, party formations and light source placements, it being all perfectly abstractable down into less granular mechanics – purely discretionary encounter placement; allowing any character trained in perception to contribute a proficiency roll regardless of their positioning and keeping the highest result; employing a single “collective light radius” modified by the number of sources, again without placement being relevant, the list goes on.

However, this is one of those cases where I’m willing to brave the muddy waters of “more is more” and retain the complexity for the sake of tactical engagement with the delving experience, one where judicious use of spikes, barred doors, alarm spells and improvised traps in conjunction with clever positioning of lookouts and sources of light, careful choice of party formation and disposition within a room can all serve to influence both the encounter chance as well as its potential spotting distance intervals, allowing a savvy adventuring group to exploit the chokeholds of a dungeon’s topography to engage in unfair fights or selectively keep some of its weaker elements out of harm’s way, allowing, in essence, mechanically meaningful answers to tactically interesting questions that arise from delving.