Constructing custom encounters – A treatise on interesting encounter creation

So, in advance, I apologize for my lack of formatting and my rough writing skills. I’ve only been writing technical manuals and documentation for the last several years, and even my campaign notes are dry as fuck.

If you don’t care about my muttering and rambling about the old editions and current editions of the game, you can skip all of it and get to the meat and potatoes of the article here:

"The problem at the table"

In my Shattered World campaign, I’ve done a lot of research into what we term “wilderness encounters” from various editions of Dungeons and Dragons, and I’ve come to a conclusion.

Which I will frustratingly get, as they say, to the point on later.

First, let’s go back to the OG ODD version of “encounters”.

ODD “encounters”

Starting with “Book 2 – Monsters and Treasure”, you’d determine an encounter based on the type of creature selected by the Dungeon Master – and there were no tables involved.

If you ran into bandits, they appeared in groups of 30-300, and had a 15% chance that they were “encountered in lair”.

So, rolling up this encounter, you’d end up with (per the example given) 187 bandits. Six would be 4th level fighters, Three would be 5th or 6th level fighters, and one (the leader) would be 8th or 9th level. Many had magical items. And “in lair” might be a ruined fortress, like this one I absconded with (thanks, Dyson) for my campaign on The Borderlands:

At this point, we’re talking a full-fledged adventure scenario. Even a one-shot equivalent to The Delian Tomb, if they’ve kidnapped a merchant from the road and taken him and his goods back to their fastness.

This type of generative narrative is important to encounters; and also key to how I feel encounters are supposed to work.

Obviously, no DM worth their salt is going to say “there are a couple hundred bandits in front of you first-level players”.

Seeing such a result, I’m only assuming a dungeon master from the time would spin this into a narrative; we’re talking people who have read hundreds of short stories, possibly thousands of books, and have dreams of Fafhrd and the Grey Mouser, and worlds without number spinning in their heads.

I’d even go so far as to create tie-ins to the main campaign story as to why they are just a few miles south of The Keep, watching the place for unwary travelers, perhaps, or an opportunity to draw out the guardsmen within and take over The Keep.

Or as I did it, simply to keep an outpost for their illicit drug-trading and slaving operation, run by a trusted lieutenant. The main contingent is back at the Caves of Chaos, and this small outpost is the first encounter of many with the Band of the Bloodied Fist.

This particular group is lead by two named fighters – Terryn the Red, a cutthroat young lady seeking to make a name for herself after getting fired at a local inn for stabbing a patron who got too handsy with her, and being sought by the guard of Mollin’s Crossing for his subsequent murder. She was second in command until yesterday – when the Lieutenant was eaten by a rampaging manticore freed from the ruins further back.

The second is Rolf, a devious man who was expelled for running cons in town years ago, who now survives by joining merchant caravans as a guard and then directing the bandits on how to hit the caravan. He is a base, cravenly coward with few redeeming features and a penchant for backstabbing.

Of course, all without knowing there is a manticore trapped within the caved-in ruins further back… but I digress.

Wilderness in ODD

Now, looking over at “Book 3 – The Underworld and Wilderness”, we first see the encounter tables as designed, pretty simple in their execution. This check occurs at the end of each day, unless “afloat or in the air”, in which case two checks are made.

Curiously, however, the wording seems… more specific than the usual ODD vagueness which we encounter in Gygax and Arneson’s work from this time:

“Wandering Monsters: At the end of each day (turn) the referee will check to see if a monster has been encountered. The matrix below is for travel afoot or mounted.
For travel afloat or in the air two die rolls are made — a 5 on the first one indicates an adventure in the mid-point of the day with waterborne or aerial monsters; a 6 on the second die roll indicates that there is a normal adventure at the end of the day, and the table below is used. Exception: Ships which remain continually in water will roll but once daily for encounters, with a result of 6 indicating such an encounter.“

I find it very curious that the specific wording on this is “adventure”. Also note the final exception on ships… stating “indicating such an encounter”.

It seems pretty clear to me that ODD wilderness encounters, wandering monsters, and “adventures” (i.e. one-shot) were synonymous in the parlance of ODD.

Expert Rules Wilderness

Ah, good old Moldvay and Cook. One thing I found particularly great about their stuff was that they loved categorizing and simplifying rules.

They equate the wilderness encounters to wandering monsters; which now makes this very interesting from my perspective.

Because none of those rolls which occur determine the number of creatures encountered. They only determine what is encountered, and (going back to ODD style) the type of monster encountered determines its “number of appearing”.

For example, there could be up to four white dragons encountered, or nine bandits, with the numbers “adjusted based on the party size at the DM’s discretion”.

Keeping the link between the creature to the “number encountered” is an old-school methodology; I think it’s important for sake of discussion, and possibly even key to the whole adventure/scenario.

Old School Essentials Encounters

Savagely condensed and improved, the tables are far more complex than the original BX from which it was derived.

The first roll, the D8, determines the type of encounter (not the monster encountered) and from there, the specific encounter is determines with a D20 roll.

If we’re in a swamp, and we roll a 4 on the 1d8, we encounter “Humanoids”, which per the second roll could be anything from an Ettin, to a Hag, Lizard Men, Ogres, Orcs and Trolls (to name a few).

Again, we revert to the “number appearing” as a baseline for the encounter. There’s a lot of vagueness here, which is uncharacteristic for Gavin, but let’s go with an “Orc”.

The number appearing is 2d4 (1d6 x 10) – so up to sixty orcs, if encountered in a lair. Additionally, said orcs have a leader (with 8 HP), an Orc Chieftain (with 4 hit dice), and a 1 in 6 chance of an ogre for every 20 orcs (so possibly three ogres) as well as a 1 in 10 chance of a troll (possibly three trolls).

Additionally, we’re looking at having as many females as males (so we are now up to 120 orcs) as well as two whelps per two adults – 180 orcs total in this lair.

Holy shit, this sounds like a major adventure!

As a DM, how would you want to handle this? At the table, with random rolls, saying “you see campfires in the distance”?

The problem at the table

Obviously, I want fun encounters and adventures at the table for my players. I want to give the world life, feel like even the “random” stuff is meant to be there and can spin off into a side adventure, if the players decide to pursue it.

Encounter tables in and of themselves can’t create that, unless you are very good at improv (I am, but even this can stress my limits) and coming up with plots on the fly.

What I propose is doing a bit of prep in your world to generate adventures, encounters, wandering monsters (used synonymously in earlier editions) before they are needed.

The Steps

Starting with the area where the adventure lies, we are going to create a “wilderness encounter table” from scratch, using the OSE encounter tables as a base, and then fleshing them out.

Step One: Determine the Terrain Type for the overall table

First, the “wilderness type”, which for The Riven City, will be a swamp. Decidedly a swamp. Since I love ominous names like “the Fireswamp”, I’m going with “The Shattered Fens”, since the area is, well, swampy and broken.

While the Riven City is just half the distance overland versus the Caves of Chaos, the actual travel time is going to be much, much longer. Fens are notoriously horrible to traverse, so each hex is taking (at six mile scale) half a day or longer to get through. Horses won’t speed this up (q.v. Artax) and boats will get grounded at regular intervals – even flatboats will require hours of carrying to get to another watery part.

No one has ever thought that they needed to traverse this area, so no one’s bothered with roads or paths. There are easier ways to get to the northern pass via the forests, there’s just a large body of water to the West, and the east is the borderlands – so no huge amount of trade or other activity to support.

Step Two: Determine how many “encounters” you’d need to customize

This part is pretty simple – most go with a 1d10 or percentile, I prefer 2d6, giving 11 possible results, for simplicity. If you have a larger area, or a longer-running game, 2d10 or even 3d6 might work better for you to create unique encounters. These tables can be updated with “used encounters” removed, and new ones added whenever you feel the need.

In my “Chavez of Chaos” portion of my campaign, I resorted to building in the “chance of encounter” into the table, so my results looked similar to this:

I learned a lot about “median” and “standard distribution” when using these tables with my group, so I highly recommend not doing this.

I suggest keeping the standard encounter roll, and supplanting it with a straight encounter table. There are also a lot less encounters to create, and the process will be much faster.

Step Three: Roll the encounters per the Wilderness Encounter Table by Terrain

Starting off with a basic table for this, I roll on the encounter tables in Old School Essentials under the “Wilderness Encounter by Terrain”.

For my first custom table entry, this gets me a result of “Swimmer”. I then roll 1d20 on the “Swimmer” table, and I get “Alligator”.

Step Four: With the result, create a scenario with a hook should the players interact with the encounter and determine the tone of the encounter

In this case, we have alligators. Normally, you would roll on the reaction table and see if this encounter is hostile, neutral, etc. and I do this ahead of time to determine the scenario: And I get a result of 8 (Indifferent, uncertain). So, that’s how I’m writing my scenario.

Some things I leave to the players to determine, and other things I will improv on the spot based on how the trip is going so far. Who are the “travelers”? Might be lizard men, might be halflings. I’m going to leave that vague for the purpose of this encounter, because I can flesh that out on the fly based on either the story events, previous rolls on the rumor table, and so many other factors.

The key to this is making it open-ended, so you aren’t locked into a use for this encounter. It can be part of the adventure, or it can be just a random event.

If you need examples of how scenarios work, I recommend reading The Alexandrian’s article “Don’t Prep Plots”.

Either way, this is a hell of a lot better than “you encounter (dice roll) … four alligators. Roll initiative.”

Step Five: Do the next entry on the table

Continue populating the table by rolling for the encounter, rolling reaction (what I call “base reaction”) and you get something like this:

The trick is to take your time, and generate these adventures as ideas pop into your head. Instead of fleshing out every one in one sitting, you can write down the base encounter as an entry like:

6 – Lizardmen – Hostile

Don’t be afraid to toss the wildest things out, but remember, leave them open-ended as to causation, intent and purpose.

Also remember that you’re not tied to the dice result. Those are just inspiration – if you want a shambling mound or a green dragon, go for it, toss it on the table. Just make sure that there is a scenario attached to the thing. The setting makes an encounter memorable.

What’s more interesting, an immature green dragon coming out of the swamp and attacking the players?

Or an immature green dragon stuck in a hunter’s trap, fighting off gullygugs who are attempting to tie it up for a feast?

While I’m applying this to wilderness encounters, as you may have seen, this can be applied to wandering monsters, encounters, or even starting a new adventure.

And every “random encounter” in your game can be memorable and unique.