Environment Design: Alternative Encounter Building III

Environment is arguably the most diverse and impactful area of encounter design. Yet, it’s the one that’s most overlooked. Spend time browsing D&D content online (blogs, subreddits, and forums) and you notice most encounter design discussions focus on balance issues and adjusting challenge. They make no mention of the environment.


If you haven’t read the first two entries in Alternative Encounter Design what are you doing? Read Part I and Part II first.

Combats don’t happen on an empty, infinite plane. And you can use the environment to dial-in the difficulty of your combat encounters. But, the environment aspect of encounter design can be very complex. The mercurial nature of environmental bonuses can scare off new gamemasters. And unfortunately, if a gamemaster never experiments with the environment of a combat it will never enter the GM’s game.

Not to fear, we can break environmental design into four, straightforward dimensions.

Dimensions of Encounter Design

  1. Distance
  2. Elevation
  3. Path
  4. Sight


This may come as a surprise, but encounters can start with opponents farther than 60 feet apart. Check out popular streams and flip through a few published adventures. How many combat encounters start with the more than 60 feet between the party and the opponents? The max range for many spells and weapons is in hundreds of feet.

Now, consider the importance of a good bow and horse.

Scaling the distance adjusts the advantage between melee and ranged combatants. Imagine starting combat at the maximum range of a longbow, 600 feet. The average melee combatant would need to take the dash action for ten rounds to close the distance. That’s a lot of rounds for an archer to take free attacks. Not to mention spellcasters with even more distant reach.

Consider this cool encounter, the party dashes between points of cover to close the distance on a group of enemy archers.

Conversely, starting close allows a melee opponent to immediately pounce on a ranged attacker. This forces the ranged attacker to make attacks at disadvantage.


The quickest and easiest way to add interest to your combat encounter is to take 2d combat into the third dimension. The most obvious example is using flying creatures, but there’s more. Consider the previous example where the party is closing in on a band of archers. Now, imagine that scenario on the z-axis. The party needs to scale the outside of a watchtower as defenders shoot arrows, drop rocks, and pour boiling water down on them.

When adding elevation to an encounter consider the different ways creatures can change elevation. Is the elevation change a natural slope or a constructed ramp? Did the creatures build stairs or an elevator to reach the next landing? Did they use a ladder or a knotted rope they can pull up behind them. Imagine it’s a sheer face; the interior stairs inaccessible to the party.

Elevation intrinsically increases or decreases cover bonuses. A watchtower archer behind a merlon has serious cover from those on the ground. He can also see and shoot arrows over a low wall that provides cover against archers at ground level.


Path dictates the width of your battlefield and how creatures navigate. Avoid getting stuck in the combat box. Encounters happen on floor plans beyond rectangles. Add circles, multi-sided arenas, or compound, shifting shapes. Consider modeling the floor plan after letters and numbers. Build the Path using obstacles, difficult/impassable terrain, and walls.

Changing an encounter’s Path can provide advantage or take it away. Consider a battlefield that’s a patchwork of small pillars jutting out of lava. Combatants must hop across the pillars to engage one another. Or, use bramble bushes as a fortification for your baddies to hide behind.

For design ideas check out the Index Card RPG from Runehammer Games. It features stellar, system-agnostic, GM advice. It also includes a section of “Encounter Archetypes,” that help to showcase Path. Check out the RuneHammer YouTube channel. Hankerin’s art background and simple design philosophy provides a refreshing approach to GMing.


Sight is more than line of sight. Vision is our primary way of collecting information about a place. Obscuring sight decreases what we know about the environment. It can be fog, heavy rain, claustrophobic jungle flora, or simple darkness. Spend a few minutes learning or making a reference for the cover and obscurement effects.

It’s easy to see the influence of Sight through cover and obscurement. Melee combatants stumbling through heavy fog to attack shadowy figures. A wizard dropping a fireball behind fortified ramparts to attack archers. The party pulls up back to back as growling, yellow eyes circle them through deep undergrowth.

A favored environment will go one side a strong advantage in combat. A fortified environment will give one side a definitive advantage. A fortified opponent’s advantage should make your players question whether to engage or investigate how to bypass the challenge.

2d6 Combat Environment

  • 2 > Opponent Fortified
  • 3, 4 > Opponent Favored
  • 5 – 9 > Equal Footing
  • 10, 11 > Party Favored
  • 12 > Party Fortified

Dangers: The Bonus Dimension

Not covered in the above discourse are traps and hazards. But, both can enrich your combat encounters and dungeons as a whole.


One way to increase the difficulty of a combat encounter is by including a trap. It could be a simple pit trap enemies try to maneuver the party towards or a magic missile turret that blasts at the end of each round. Traps can also be something the bad guys have to actively engage with during combat. The occasional combat encounter centers around a warning bell. The party must both defeat the enemies and keep them from sounding the alarm (which summons reinforcements). Many video games use a similar theme with machine gun emplacements. The stationary weapon does nothing on its own, but a single enemy can be potent when using it to fire on the party. However, the party can kill the baddie and turn the special weapon on the bad guys.


D&D is full of hazards. A hazard is basically a non-intentional trap. A hazard can be either dangerous to both sides, or just one side. Combat atop rickety scaffolding? Goblins and PCs make the same wet splat sound when they fall from great heights. Fighting constructs in a mine filled with poisonous air? Well, that’s one sided. Constructs don’t breathe and they’re immune to poison. Consider a fight of incorporeal shadows chasing after the party as an old cathedral crumbles around them. The party dodge falling debris as shadows phase right through chunks of stone moulding.


Thanks for reading part three of Alternative Encounter Building. If you’d like to refresh your thoughts on the first two posts you can find them here: Challenge Rating and Odds. You can also follow me on Twitter.

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