The Architect DM: Traps, Hazards, & Terrain

Once again I solicited on my twitter account (@Bartoneus) asking what aspects of location design in RPGs people have problems with, and I’d like to thank everyone that responded this afternoon. I will be addressing many of the topics you guys asked about in the future, but for today’s post I chose DigitalDraco’s comment: “I always want to include more interesting terrain effects, hazards & the like but they tend to seem added-on.” This topic immediately struck me as one that I’ve struggled with in the past and one that I believe many other people have had issues with as well.

The great thing about traps, hazards, and terrain effects are that they can be direct personifications of the environment that metaphorically (and sometimes quite literally) bring the world around your characters to life. First the best idea is to clarify some definitions that I feel are pretty widely acknowledged. Traps are typically intentionally malicious effects that were orchestrated by a foreign will or entity for a specific purpose. Hazards and terrain are generally considered to be natural but they can just as easily cross over into the realm of traps in the same way that traps can cause hazards and changes in terrain. Focusing on and playing up this potential inter-relationship of traps and hazards/terrain is my first recommendation for creating interesting locations that include these elements.

Connectivity Breeds Realism

What I mean by the above title is that tying elements of your design together can justify all of those elements even when they relate to very little beyond themselves. This is a direct suggestion focusing on the last part of DigitalDraco’s statement, “but they tend to seem added-on“. If you have added one element to a location and it seems added-on, try adding another element that relates directly to the first and you might find that instead of both of them feeling added-on, they start to create a new definition of the location you’re designing. I also recommend treating the main topics of this post as a set of guidelines when adding elements into encounters, if the first thing you’ve added is clearly a trap, the secondary element you add will probably fit better if it is a hazard or a terrain effect. If you’ve added a hazard, the secondary element may work best as a trap or a hazard.

For example, you are absolutely dying to use a massive explosion as a part of a trap in your next encounter. Let’s say you run the encounter and you’ve planned the trap really well, it goes off well, but you can’t help but feel that the massive explosion feels added-on and out of place in the encounter. Yes, we’re suspending our disbelief that explosions could ever be NOT cool, and we’re ignoring my favorite Rule of C4 (adventures with explosives are always more enjoyable). Now imagine if you have the trap set off, a large explosion occurs, and as a result of that explosion the entire terrain of the encounter is changed in a drastic way. Maybe the ground is blown away to reveal a massive cave below or the structure all around partially collapses and gives the characters easier access to an upper level. If you want to go the hazard route, you can have the explosion open up the ground to an underground river below or maybe the explosive included some kind of napalm that continues to burn across the ground of most of the encounter. Many of these elements may not have a direct relation to the location itself or what the characters are doing, but in the act of linking the two elements together you have further integrated them both into the encounter.

Another way to think about this, and one that focuses less on the stimulus of requiring a trap to go off, is to add some life to the hazards and terrain that you put in your encounters. Adding a flowing river to an encounter can be great, but if it’s just sitting there on the edge of the map then the players may never interact with it or even if they do it can still feel incredibly tacked on to the whole thing. Give it a life of its own! Have your river surging against the land around it and once every round or as often as you like have the rushing waters break off some of the ground and carry it away in the current. Don’t be afraid to turn your terrain effects into hazards or have you hazards leave various terrain effects in their path. We see this mentality in many types of encounters these days where rocks falling from above are a clear and threatening hazard and after they occur they leave difficult terrain in their path. Take this idea and adapt it as much and as frequently as you can. One simple change can be to have the rocks fall through the ground and open it up to a chasm below, instead of leaving difficult terrain these falling rocks end up leaving much more threatening openings in their place.

A Little Fluff Goes a Long Way

Some of the elements that seem most at risk for feeling “added-on” in your locations are those that you find published in books (typically Dungeon Master Guides), things like Blood Rocks and Fey Circles that feel like pre-packaged elements and effects because that’s exactly what they are. One of the simplest ways to incorporate these into an encounter is to add just a little bit of location fluff around them. Instead of simply putting a Blood Rock into your location, put a Blood Rock and then describe or draw on the map large veins of blood or red arcane energy pulsating out from the Blood Rock. These veins don’t necessarily have to do anything, but wherever a character is in the location they will have a connection to the Blood Rock, and perhaps stepping on one of the veins conveys a small effect or the character hears a voice calling them towards the rock.

If you’re following my earlier advice, you may decide to include multiple Blood Rocks, and the veins across the ground can connect all of the rocks and pulse with energy every few rounds as the rocks themselves pulse and release extra energy. These elements need not be integral parts of the location when you start designing it, but by the end of it they have become just as defining a feature of the encounter as any of the other elements you include.

Don’t Be Afraid to Improvise Traps and Hazards

The last bit of advice I have on this topic for today is that if a good opportunity arises to throw a trap or hazard into an encounter, take it! Certainly there should be some hesitation with consideration towards over-complicating a situation, but if it is a normal encounter and one of the characters knocks a column over you can easily throw some collapsing ceiling and/or difficult terrain into the mix. If a player makes excellent use of an elemental spell, and the situation seems to call for it, have it linger and become an interesting part of the encounter dealing out elemental damage or causing other interesting effects. As a result, that player may end up being more attached to the action and if things go really well they can even feel a bit of ownership and responsibility when it comes to how that encounter played out.

These are good feelings for players and DMs alike to have, and that’s why I encourage you to allow players to interact with the environment as much as possible and change things as you play. Let players set up traps or alter hazards and terrain if they show even the slightest inclination towards it.

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  1. I like traps, or at least the idea of them, but one of the things that gets in the way of me using them more has always been the reasoning behind them. Many of the adventures that I’ve attempted to use have traps that seem out of place, not just added-on. For me, the idea of the people living there dealing with a trapped area on a day-to-day basis seems ridiculous and unrealistic. Ancient tombs, decoy doors or chests are acceptable because they’re special occurrences. That one hallway leading from the kitchen to the laundry though? That’s just absurd. When designing my own dungeons can rarely justify putting traps in because they don’t make sense for the original inhabitants, and the new ones would never bother with it. I’m never sure how to employ them more without my mind raging against them.

  2. Thanks for sharing your thoughts – I’ve had similar concerns. I really like the idea of filling in details around the hazards, and making them a little more intricate. I’ve made a sort of master list of different gimmicks I can throw into combat encounters, including all the special terrain and some other interesting angles (like players slowly losing health, or fighting the current of a river).

    Having at least one interesting way that the setting interacts with the mechanics of combat seems to do wonders for my players. They love that sort of thing. And I think you’re spot on – if they can have some sort of lasting effect on the setting of the encounter, they grin from ear to ear. I find terrain effects to be the easiest to implement without risking a break in realism, but hazards and traps (especially some of the “haunting” ones found in Open Grave) have been cool to use.

  3. @Jess: One thing to consider is using traps that are “activated” by the dungeon’s inhabitants. In other words, the trap door that opens up to the 50 foot pit is only triggered if somebody flips the switch. Alternatively, some of the blaster traps presented in the DMGs work well as they can be attuned to the inhabitants (i.e. it won’t attack dwarves, etc.). But yes, I agree that when invading the evil baron’s keep it doesn’t make much sense to have an explosion go off if somebody steps on one of the black tiles in the hallway (unless this was somehow activated by the baron and/or his troops).

  4. I like using obvious trip wires… to disable the trap.

    “You see a wire across the hall.”
    “I step over it.”

    From Grim Tooth: Flint Golem… swamp gas… steel swords… boom!

    Integrating terraintraps can be hard. I created sticky mushrooms, if you run into them… you’re immobilized (save ends). This lets you have more fun with your monsters.

  5. I like integrating natural elements into a setting. The idea is that your players will role play through what they do while camping or otherwise dealing with a difficult situation. This is easy to set up… make sure the players loose some equipment and provisions, then start tracking resources. They need food, water, and shelter.

    If you were trying to set up some passive traps at the entrance to your tomb you’d probably look at Food, Water, and Shelter sources. Right?

    If you want butterflies in your garden, you will need to plant butterfly food. (This fact is often lost on gamers.)

    If you want to make an area unpleasant in an effort to guard it, you can set up a series of natural traps. Place a Vine Horror next to the Apple Tree. A mango tree full of Griffin Bats (harmless)… Poison the water well. Place giant crocodiles in the marshpond next to the ruins.

    Traps should be designed to eliminate potential threats. That typically doesn’t include adventurers, but rather 0 level grave robbers. I feel that traps should function naturally and even be single use. (I’m not a fan of fully automatic magic bolt launching turrets.) Falling logs, one way swinging blades, etc, make sense. (The rolling ball in Raiders of The Lost Arc fits this description.)

    Back to nature… Mango trees attract bats… what if that particular bat was called a “Griffin Bat” so named because it attracts Griffins. Under trees are also a great place to sleep at night… It doesn’t take much to see that fun will ensue. (Remember that the Griffins won’t be coming in to start a fight, but they’ll likely step on some sleeping adventurers.)

    After the players figure out the bats, don’t forget to mention the Dragon Fruit.

    I’m a big fan of undead in dungeonstombs. I think they need to be mixed with other stuff for some real entertainment. A tree full of Stirges, and some zombies on the ground (with no hands). They’d naturally unintentionally work together. This kind of ecology makes a lot of sense.

    So the players set off a blasting trap at a door… Pushing them into the stcky mushrooms 20 feet behind the door. (Immobilize Save Ends) Out comes a legion of crawling claws. (Remember the zombies with no hands under the stirge tree?) After that mauling, they decide to camp in the ruins under the mango tree. After some butt kicking with griffins, the water flasks are wrecked… the cleric takes off to the well to get some water… *blech* i falls over fibrillating on the ground…

    We haven’t even gotten into the dungeon, and the players are already dealing with a series of unfortunate events. Many of which don’t even appear to be traps. That’s the stuff memories are made of.

    A final note: Often people overlook the purpose of the trap. In old D&D it was typically instant death. In 4e, its to entertain, and consume player resources (like healing surges and equipment). So keep that thought in mind as you put this stuff together. You may need to change the DC of a trapencounter on the fly to suit the amount of ‘entertainment’ the players have had.


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