Hidden Secrets

Yesterday, I read a great and somewhat surprising post on the Tao of D&D. It was surprising because it got right to the point and dealt with meaningful issues. Except, of course, it turned out that it wasn't on Tao of D&D... I just mistakenly believed that, for some reason. It was on Hack & Slash. (Sorry for thinking you were Alexis!)

Anyway, one thing that jumped out at me from that post was a distinction near the end between two types of concealment: hidden vs. secret. A hidden door is automatically found if someone searches the area it is in. A secret door is only found on an appropriate roll.

I don't run it quite the same way, but the distinction still stands: I treat things that are secret differently than things that are hidden, and hidden things can be fairly easily found. We all have a pretty good idea what "hidden" means. But what, exactly, makes a door or compartment or other item secret, instead of merely hidden?

For me, it's not that secret things require a die roll. It's that finding them does not necessarily allow you to use them, or even know what they are.

"You find a hidden door." It's behind a tapestry or covered with plaster or something, but once found, it's pretty obvious that it's a door. If there's no knob, it might be difficult to open, but you at least understand the concept.

"You find a secret door." Actually, it might not be a door. What you find is a section of stone or wood paneling or whatever that looks different. If it's a door, you don't know automatically how to open it. It might not be a door, it might be a pressure plate that triggers a trap. Or it might be a secret compartment, Or it might be a sealed doorway/compartment, with no mechanism to open, just a hint that there's something behind it (fetch the sledgehammer...)

Finding a secret door isn't automatic for general searching. The point is that it doesn't look that different from the rest of the wall, floor, ceiling, or other feature that it's part of. That's why there's a die roll. But finding it might be automatic with other methods, depending on the details of the secret. Secret door with a light source on the other side? Dousing all the light sources on *this* side automatically detects it. Windy area on the other side? Candle flame will flicker as it passes near the cracks. Secret compartment in stone wall? Tapping it makes a different sound than tapping around it. There's no single method that will automatically find every secret door, other than magic, maybe. But for every secret door, there's at least one method that skips the die roll.

But the real difference between hidden doors and secret doors is the mechanism for opening. My "default" secret door is the pivoting section of wall; as long as there's no locking mechanism, it opens automatically when pushed on the proper edge. Sliding panels must be pushed and slid in a specific direction. Mechanically operated secret doors have the cliché wall sconce, hidden crank, or other trigger that causes the door to open. Magic secret doors either open when a magic word is spoken or action performed, or the magic word/action unlocks the secret door, allowing it to be opened by pushing or sliding.

Mechanical secret doors can be automatically found if you find and operate the trigger. Consider for example a secret "portcullis", a section of wall that raises when an hidden crank wheel is turned. Finding the crank wheel may be easy, if you search the right location. The secret door becomes obvious if you dare to crank the wheel, opening the door.

20 Questions, Part V: Magic and Miscellany

Here's the last part of my answers to the 20 questions:

15. How are traps located? Description, dice rolling, or some combination?
    5+ on d6 when blundering along or to notice hidden clues when moving carefully. Other actions make traps noticeable without rolls: see my post on search techniques.
16. Are retainers encouraged and how does morale work?
    Get retainers, get hirelings! Typical hirelings desert on 5+ (on d6) when any hireling is injured (use damage roll,) or when facing magic, supernatural, or superior forces (separate d6 roll.) Extra roll if leader seems to be defeated or betrays them, or if party takes 50% losses, and again at 90% losses. Loyalty determines morale adjustment.
17. How do I identify magic items?
    Standard spell research rules, for safe ID. Otherwise, trial and error.
18. Can I buy magic items? Oh, come on: how about just potions?
    If you can find an M-U, you can buy scrolls. Potions usually require a wizard, who is much harder to find, but a priest may have blessed healing potions. Otherwise, you must commission magic items from a wizard.
19. Can I create magic items? When and how?
    M-Us can make scrolls at any level, 100 gp/spell level. Otherwise, only wizards can make items. Use standard spell research rules.
20. What about splitting the party?
    Probably not a good idea, but you can risk it. Avoid secret communication whenever possible.

I won't cover searching for traps, since I've covered it in detail earlier. The d6 roll is basically a save, not a skill roll. The morale rules are standard, except that I've switched to 1d6 to make such rolls easier; I can use the damage roll for the first person struck to determine what the hirelings do, and if there are large groups, roll a handful of d6s, 1 per 5 hirelings, to see how many bolt. I also use this as a "following orders in combat"  test, when things get confusing. The TPK featured the fleeing hireling not dropping a bag of treasure that the players suspected was cursed. He didn't register what he was hearing for a while.

The magic rules are mostly pretty standard, except that high-level NPCs are rare and I've added the Holmes modification to scroll creation.

If the players split the party, I try not to use note-passing or pulling characters aside for secret sessions. I don't generally care if some players hear the description of a monster only one character can see; if they're fairly close, I assume there's some shouting, and if they're far, the other PCs can "on a hunch" run to help another PC. It keeps everyone involved. The recent posts on doppelgangers and possession indicate some of my thoughts on how to avoid secret communication even in more extreme situations.

Magic Traps

I'm not sure there's much I can say about magic traps, compared to the physical trap triggers and effects I've been describing for the last couple weeks. It's not that magic traps don't have as much variety as mundane traps (quite the opposite!) But magic traps get their variety from the enchantments used as triggers and trap results; the way a magic trap functions, on the other hand, is pretty simple, as is the way it is detected.

The simplest magic trap is an object created by magic that is dispelled after a set time or when a set condition occurs. For example, a wall or floor created with Phantasmal Forces will vanish when touched by a living being, allowing pit traps covered by false floors, or blinding light sources obscured by false walls. Another example would be a trap door in the ceiling which opens naturally under the force of gravity, but is held shut by a Hold Portal spell; when the spell ends, the door opens, depositing whatever was resting on it down below. An inverse example is a Wizard Locked door that is ajar when found; closing the door for any reason prevents returning down that path. Other magical effects that last longer than traditional spells or which end when specific conditions occur would fit here, too; magical water that raises when anyone not bearing a golden trident enters the room, or a pillar of ice supporting a (physical) lever that lowers when the ice melts (perhaps triggered by bringing any flame larger than a candle within ten feet...)

Next up is an otherwise ordinary trap where the trigger or the link from the trigger to the actual trap is replaced with an intangible, magical connection. Take, for example, a magical floor tile which causes a slab to rotate whenever someone steps on it. The effect of the intangible connection is that it removes pulleys, gears and levers that might otherwise be detectable, plus it can make it difficult to determine what the trigger actually activates. Another for this variant is to limit ordinary traps to highly-specific targets. Physical triggers can be set to trigger under a specific weight, or after a specific delay, or the trigger can be positioned so that it can only be tripped by creatures of a certain height; magical triggers may be "dwarf only" or react to (or be disabled by) a specific password.

Then there are traps with magically-created results. The infamous Magic Mouth is one obvious example, producing sound when a particular event occurs; others may resemble physical effects, but the effect comes from nowhere (traps that throw endless fireballs or lightning bolts, for example, or Exploding Runes.) Many State Effects are produced magically, which is why the previous trap effects post specified Physical State Effects; Magical State Effects, like freeze traps, work differently.

There's also the petty example of an ordinary physical trap with various components made resistant to damage via magic, or which is reset magically.

The main difference between magical traps and physical traps is that the magic removes one or more physical clues, often making the trap much harder to detect. However, magic itself is a detectable feature, via a Detect Magic spell or some other means. We can consider a Mag/S detection method as equivalent to Odor/S, Warm/S, or El/S.

Traps: Physical State Effects

You may have noticed that the other three result types can all be expressed in terms of objects moving into the target space (Material Effects,) structural elements moving in or around the target space (Structural Effects,) or victims or their possessions being moved through or out of the target space (Motion Effects.) But some physical changes do not involve spatial changes at all; they involve changes of state, such as light, temperature, humidity, air pressure, noise level, odor, magnetic properties, or other sensory qualities named as trap detection methods.

Audible State Effects create noise, either as an alarm, as a distraction (to cover the sound of monster movements, for example,) or as a trick; extremely loud noises may even act as a weapon, stunning or causing damage in those who hear it.

Visible State Effects would include light or color changes, such as a bright flash to blind victims or a projection of a shadow to trick them. A room can also be lit to begin with, perhaps luring adventurers into dousing their torches, only to suddenly kill the lights right before they enter a room full of pits, or before releasing a monster.

Odorous State Effects can be odors designed to trick victims into believing a dangerous monster is nearby, scents to mask a real danger, or odors that have a side effect, such as sneezing or gagging.

Warmth State Effects or temperature effects involve increasing or decreasing the temperature of an area to make it unbearable or even cause damage. This could be wide area (an entire room reduced to frigid levels, to cause hypothermia,) or it could be a very focused target (heating a metal door handle to make it impossible to open without causing damage.)

Electrical Effects work in much the same way. A subcategory, Magnetic State Effects, can be used to slow or halt movement of victims wearing metal armor.

Tactile or Gustatory State Effects probably won't be stand-alone effects, but will be included with another effect, such as painful light or noise.

All of these are physical state effects and generally based on some kind of Material Effect. For example, temperature effects are usually accomplished through superheated air or boiling water, and gagging odors are usually produced with odorous material. If the material is introduced directly into the area (pouring boiling water on victims, for example,) State Effect traps are detected in the same way as Material Effect traps. However, many state effects involve the indirect application of materials, such as pumping wretch-inducing sewage into pipe beneath a floor and only allowing the stench to escape. These indirect trap effects are often more difficult to detect, since the material that produces the state does not have to enter the room.

The subtype of state effect is of course detectable by the named sense. A trap that produces a blinding flash involves some device that is visible, so it should be detectable by sight (Vis/S.) Some traps that have been used previously, but are not currently active, may leave lingering signs of their effects: the wretch-inducing sewage may leave a faint odor after it is pumped out of the area.

Traps: Motion Effect

Traps with a Motion Effect affect the movement of a victim. These are distinct from traps that move an object or substance into or out of a room (Material Effect) or move walls, floors, or ceilings that compose a room (Structural Effect,) although either of the latter two can have a Motion Effect as a side effect. There are two practical forms of this trap result: Impeding and Repositioning.

Impeding Effects slow the victim's movements or otherwise make them difficult. Caltrops, for example, can potentially cause damage, but this can be avoided if the victim slows movement to avoid the tiny spikes. Marbles or an icy surface either slow movement or introduce a risk of falling. Waist-high water slows movement, but has no risks unless the victim is knocked unconscious. Most Impeding Effects depend on a Solid or Liquid Material Effect, so detection is pretty much the same: typically, Vis/S to spot a shutter or valve that releases the caltrops, marbles, or water, Aud/S to hear them as they rumble or pour down the pipes. Damage-causing traps aimed specifically at the legs can have an indirect Impeding Effect as well, and may have entirely different chances and procedures for detection. A rotating floor or conveyor belt, or a trick staircase that turns into a slide, uses structural elements to impede movement and thus might be a little easier to notice, but difficult to avoid or disable.

Repositioning Effects change the location of the victim in some way. Chutes are Repositioning and Diverting traps, covered pits are Repositioning and Blocking traps. Repositioning Effects based on Solid Material Effects often cause damage as well (log attached to ropes that acts as a ram, causing 1d6 damage and knocking victim to one side;) those that depend on liquid or gas usually involve a blast of fluid and are less likely to cause damage.

There's a theoretical third type of Motion Effect; instead of reducing movement, a trap could increase it. I can't think of an example of this or how it would be useful, unless you want to include the trick staircase that turns into a slide which does not cause an immediate drop, but instead forces victims to choose between moving at double speed with a risk of falling, or half speed with no risk. Another theoretical example could be a canal with a gate that can be opened to increase the waterflow, making it difficult to reach a particular disembarking point and instead hurtling the victim's raft over a waterfall; however, that might be better classified as an Impeding and Repositioning Effect.

Traps:Structural Effect

Continuing with trap results to pair with the trap triggers previously described... Structural Effects are those that alter barriers, surfaces, cover, or routes in the environment. They're all fairly simple to describe and perform one or more of these functions:

• Block access,
• Open access,
• Divert traffic.

The simplest Blocking effect is a triggered tunnel collapse; variations on this effect is to collapse the tunnel floor (exposing a pit) or fill a tunnel with some material other than falling masonry (water, lava, a colossal pile of leeches.) Any of these effects are basically one-shots; a more controlled Blocking effect is the portcullis trap, which can be dropped or raised again. Similarly, a lever can lower a bar across a door, to prevent it opening. A Blocking effect trap may injure a victim caught in its path as if it were a Material effect trap, and some materials used to block access may have side effects, or may only block certain kinds of access; a water-filled tunnel will only block access to those who need air to breath and can't make it to the other side while holding their breath.

The reverse is an Opening effect, which enables access, usually for a hostile opponent. The first thing that comes to mind is probably a wild animal or monster enclosed in an adjacent room; activating a trigger releases a latch, causing a false stone wall to drop, allowing the beast to enter the area and attack. Secret doors are sometimes used in this way; an alarm can alert intelligent dungeon occupants, allowing them to use secret passages to maneuver behind an unsuspecting party of adventurers.

A Diverting effect is, in a sense, a combination of the other two structural effects. Before the trap is triggered, the adventurers have access to one area; after a wall shifts to one side, that access is blocked and a second route is opened. If the diversion is designed to make detection difficult, such as rotating or shifting walls in a maze, the adventurers may become lost and confused, unable to find their way back to a safe zone. A more obvious diversion would be a covered chute trap that opens, dropping unsuspecting adventurers to another level.

In general, structural effects have to be fairly large scale, involving entire walls, floors, or ceilings that move to block, open, or divert routes. Thus, the moving structural element will probably have visible seams (Vis/S, Vis/P if concealed.) Covered pits and chutes can be disguised with sand, mud, or other materials to prevent visible examination, but the ten-foot pole will be useful here, as might pebbles or rocks (Tact or Aud/C.) One-time effects powered by gravity, such as a stone block that seals a passageway, probably use very simple triggers which will be difficult to detect; repeating or continuous effects, such as walls that slowly rotate, will probably require very large gear or pulley systems, which will make a detectable noise (Aud/S.)

Traps: Material Effect

After thinking about trap results and effects for a few days, as opposed to trap triggers, I've come to the conclusion that there are four basic trap results that occur singly or in combination: Material, Structural, Motion, and State. Let's look at traps with a material effect first, since they're pretty common; they add some substance or material to the environment. There are basically three forms of matter, with distinct ways they may be deployed, plus a fourth form, fire, that is really just a flammable version of one of the other three forms.

Solid Matter traps thrust, throw, or dump solid objects into the target area. The simplest of these would be a deadfall, which drops rocks or other heavy objects onto victims. Weapon traps of various kinds are just an elaboration of this basic principal: a weapon is just solid matter in a specific shape, to increase damage or cause specific injuries. A third variant is sand or dust, meant to smother or suffocate victims. Occasionally, Solid Matter traps have a Structural, Motion, or State side effect (blocking a passage, knocking a victim down or into a pit, dumping hot stones into water to heat it up, filling the air with thick dust to reduce visibility.) Deploying solid matter requires either a vent or duct with a shutter or valve on one end, dumping the material into the target area when opened, or a channel or track which the object rests on until propelled out by a spring, hammer/lever, or blast of air or water. The opening or shutter that the object passes through as it enters the area will be visible, discoverable by either slow (Vis/S) or paranoid (Vis/P) inspection, depending on size and concealment; ducts or vents, or hollow compartments for firing mechanisms, are detectable by tapping (Aud/C); the movement of the object after the trap is triggered will probably be audible, depending on size of material (Aud/N through Aud/P.)

Liquid Matter traps spill, squirt or pour liquid into the target area. Simple liquids like water are less likely to cause direct damage from impact, but drowning is still a possibility, as is damage from other liquids like acid. Liquid traps are thus more likely to be used to create water hazards, making travel slow, difficult, or impossible; there are also the side effects of liquids seeping into clothing and containers, to possibly damage scrolls, spellbooks, maps, food, or other items that should be kept dry. Liquids are usually deployed the same as solids, but because they can seep through sand and other particles, liquid outlets can be completely covered, making them hard to find (Tact/C). They can also seep through cracks, which will be easily visible (Vis/N,) but easily mistaken for ordinary stonework. Once triggered, a slow-moving seeping or dripping liquid may be detectable as a spreading damp spot in sand (Vis/S) or a gurgling or dripping sound (Aud/S in most cases.)

Gaseous Matter traps inject gasses into an area. There are two basic types: those that blow gas, possibly to push victims in a particular direction or blow out torches and candles, and those that fill an area with gas to suffocate, poison, or otherwise affect targets. Opaque gasses (or smoke, which is really a solid suspended in air) can be used to obscure vision as well. Gas is deployed in pretty much the same way as liquid, but the gas vents can have tinier openings (Vis/P or worse,) and gas seeping through cracks or sand particles may be visually undetectable if the gas is invisible; there may not even be a sound, unless the deployment is quick (Aud/P even then.)

Flammable Matter traps inject materials that are either on fire now or will soon catch fire. The exact deployment depends on the type of matter, which is usually flaming oil (Liquid) or a flame jet (Gaseous,) but burning coals are also a possibility. Flammable gasses are a good option, since they are invisible and do not need to be lit if the trap building assumes the intruders have torches. If the material is not pre-lit, the ignition source may be detectable (Warm/P, or El/P for some kind of small leyden jar that produces a spark.) If it is pre-lit, the burning substance may produce more heat (Warm/S, for a specific spot) and possibly smoke (Odor/S.)

If the material in a trap has unusual properties, there may be leakage or remnants of a previous victim that can provide clues to the trap's presence or nature: debris (Vis/P;) damp spots in sand (Vis/S, definitely any Tactile search;) odors of poisons or methane (Odor/S or P.) The traditional method to detect poisonous gas is with a small animal like a canary; the animal is affected first, providing a warning of a gas leak.

Traps: Detection Methods

I thought it would be good to summarize my previous posts on trap triggers using a list sorted by detection methods, so that GMs could compare the party's behavior to the kinds of triggers they would find. (This doesn't include trap results yet, because I haven't categorized them.) The detection methods can be sorted by the standard senses, arranged according to how close you have to be:

• (Aud)ible,
• (Vis)ible,
• (Odor)ous, (Warm)th, (El)ectric (...),
• (Tact)ile,
• (Gust)atory (taste)

"Audible" and "Visible" can switch places, depending on environmental factors (obstacles to sound or light.) I place "Audible" first because it will always work, whereas "Visible" details are only visible when there's light available.

Odors generally require getting closer; figure you have to be in the same room at least, with distance diminishing for fainter odors. I also group things like sensing temperature or having your hair stand on end because of static electricity into the same category.

"Tactile" and "Gustatory" both involve direct contact, but since many poisons and potions require consumption, I ranked it as being "closer" than merely touching an object.

If you are surprised by a trap, you are caught in it; thus, you attempt to detect it beforehand, to eliminate a surprise roll. We can use the same detection methods as I described earlier, although I've renamed them slightly here so that I can abbreviate them in my sorted list:

1. (N)one, just blunder in: roll for surprise as normal;
2. (S)low Entry: no surprise roll if obviously Audible or Visible;
3. (P)aranoid Entry, stop and scan first: no roll if obviously Audible, Visible, or Odorous;
4. (C)autious Entry, test from safe distance where possible: no roll if obviously Visible, Odorous, or indirectly Tactile, or any Audible details;
5. (T)horough Tests: no roll needed for any senses, but may suffer effects.

Sensory details can be hidden by some obstacle or disguise from senses that act over a distance (Audible, Visible, Odorous, Warmth, Electric.) To make the detail obvious, a person searching must mention what they do about the obstacle. For example, a door is usually plainly visible, but a door behind a tapestry is hidden until the tapestry is moved. Hidden details also include audible, visible or other phenomena that only occur under specific tests, like a hollow sound made by tapping an object; this is why Cautious Entry detects any Audible sounds, not just obviously Audible sounds. In general, a hidden detail requires increasing the thoroughness of a search procedure by one level.

Some details can also be observed indirectly, which provides less information. For example, a backlit creature or statue around a corner will cast a shadow; observant characters will see the shadow, but not know what object is casting the shadow. This distinction is most important for tactile details; touching an object or surface with a pole or weapon only allows indirect Tactile details, such as pressure or "give".

Detection methods, sorted first by sense and second by thoroughness, and the kinds of triggers or details they discover:

1. Aud/N: really large gear or pulley systems, huge volumes of pouring water used in delays
2. Aud/S: typical gear/pulley systems or water/sand delays
3. Aud/P: short delays (tiny volume of water or sand pouring into or draining out of container)
4. Aud/C: secret ducts or compartments (tap area;) 
5. Vis/N: obvious mechanical systems of any kind, such as tripwire in lit room
6. Vis/S: obvious vent, catch, or lever; typical tripwires and pressure plates
7. Vis/P: tiny vent, hidden shutter, backlit springs, latches or other mechanics when viewed through a crack
8. Vis/C: tiny spring or lever triggers
9. Odor/S: delay that uses burning material
10. Tact/C: pressure plates (press plate, but may trigger;)  buried plates (poke through sand/mud;) hidden springs, wires, or levers (poke through crack)

I've grouped all compression and equilibrium plates together with pressure plates in the above list, since they are about equally hard to find; the differences between them mainly deal with how they are reset or how versatile they are. However, a plate that incorporates a bellows or lever might be detectable by sound as well as visually.

Traps Series

I do plan on continuing the traps series, but the next parts will probably deal with how to detect and disable different trap results. This requires some mulling over, however; I want to break delivery systems down into types the way I broke triggers down. It may take a while. Also, I should go through the posts and create a summary of the information, sorting by search procedure instead of by trigger type or result type, so that GMs can listen to how the players plan to search and look up what kinds of triggers and results they will detect.

In the meantime, here's a round-up of all the post links, in order:

• Intro
• Search Techniques
• Springs
• Shutters/Valves
• Compression Triggers
• Levers
• Pressure Plates
• Equilibrium (Balance) Plates
• Delays
• Wheels/Axles

Traps: Wheels and Axles

Wheels and axles allow a couple useful modifications to the trigger mechanisms described so far. As mentioned in the post on delays, the rotation of a wheel can be used as a timing mechanism, either to repeatedly activate a trigger after a standard duration or as part of a series of wheels (gears) designed to count off a delay.

Consider a gear with one tooth. The tooth is, in essence, a lever, which can be used to activate another trigger; the fact that it is mounted on the rim of a wheel means that, as the wheel rotates, the lever repeatedly activates the second trigger. As long as the wheel rotates at a constant rate, the duration between trigger activation events remains fixed.

Another use for a wheel is as part of a pulley, to magnify the force of a trigger, extend it, or change its direction. It can also be used to rewind or reset another part of the trap; a wheel with a crank handle that can be used to wind up a rope or chain can be used to manually raised a portcullis that has been dropped by a trigger.

One particular use for a pulley or spool system is as part of a gravity-powered delay or repeater. Start with a spool on an axle, with rope attached to the spool's hub; attach a weight to the other end of the rope and wind it up. Add a peg to one rim of the spool that is positioned to be stopped by a catch (lever trigger.) On the other rim, add a flexible bracket (spring) with a mallet connected to the end; place a bell within range of the mallet. When the catch is released, the weight pulls the rope, which spins the spool, which rotates the mallet, which repeatedly bangs the bell; the result is an alarm trap. Replace the mallet and bell in the alarm trap with sharp blades mounted on poles and you have a rotating blade trap.

If the wheel is actual a gear, or has a gear attached, it can be used with chains to drag an object, or with a toothed rail or long screw to extend a pole (for a thrusting spear trap, for example.) This would be one way to create the iconic "crushing walls trap": replace the mallet/bell in the alarm trap with a gear that meshes with a long screw; embed one end of the screw in a slab of some material. When the catch is released and the weight causes the wheel to spin, the screw is moved along a track, pushing the slab. The same principle can be used for walls in a maze that reconfigure themselves, or for elevators.

If a wheel has a hole in it, it can be used as a shutter or valve. When the wheel rotates, sometimes it will align with the hole in a container, like a reservoir filled with sand, and sometimes it will not align, blocking the hole. When the holes are aligned, sand pours through the openings.

Wheels can also be used in the delivery system (the trap effect, rather than the trigger.) For example, the wheel could be a grindstone; it would have to spin pretty fast to cause damage, though. Similarly, the wheel can be a turning platform with an upright slab on it, for another variation of the maze that reconfigures itself. A really big stone carved into a wheel shape can be placed on a ramp with a wedge or catch underneath the front end; when the wedge is removed by a trigger, the wheel will roll down the ramp, perhaps doing damage

Wheels used as turntables are, in general, as easy to detect as pressure plates and related triggers; the crack between the turntable and the rest of the floor is usually visible. Wheels used as rotating shutters are sometimes even more obvious, depending on the thickness of the wheel or any wall covering it. Other wheels are generally hidden behind walls, ceilings and floors, so they aren't readily visible; they will, however, make a noise as they turn.

Wheels can sometimes be jammed by wedging an object between the wheel and another surface, but if the force rotating the wheel is strong, the wedge may simply be smashed or ground up after only a short delay. If the wheel has an axle that is exposed to access and can be damaged, the wheel can be prevented from spinning. Otherwise, adventurers should concentrate on disabling the trigger that causes the wheel to turn or the trigger activated by the turning wheel, rather than the wheel itself. Or, of course, avoid the trap entirely.

Traps: Trigger Delays

Adding a delay to a trigger pretty much just involves knowing how long some event takes to finish and setting up a mechanical test for completion. In pseudo-medieval settings, it's probably going to be one of these three:

• Quantity: How long does it take for a container to fill or empty?
• Consumption: How long does it take something to be used up?
• Speed: How long does it take for an object to travel a given distance?

The quantity test usually involves a container sitting on a compression or pressure trigger (activated when enough weight has been added or removed,) or a container with a lever trigger inside it (activated when the contents of the container reach a certain height.) For example, if a trap designer knows how long it takes for water to drain from a barrel, the designer can place a float in the barrel attached to a lever, exactly as you would see in a toilet tank, and connect another lever trigger to a cork in the bottom of the barrel. When one lever is tripped by, say, an adventurer opening a door, the cork is pulled and the water begins to drain. When the barrel is empty, the lever on the float reaches its "triggered" position, triggering a trap to go off. This allows a trap designer to make a portcullis drop 1 turn after adventurers have entered a room, for example. Alternatively, a trigger can be designed that drains a small amount of water into a reservoir each time the trigger is activated; tripping the trigger a certain number of times fills the reservoir completely, raising a float lever to the proper height and triggering a trap. Other substances can be used, for example sand in a trigger that must sit unattended for years, or pebbles dropped one at a time onto a pressure plate.

Water that empties from a barrel can also be seen as a consumption test, which provides clues as to how to set up other such tests. For example, instead of draining a barrel, a trigger can merely open it and allow the water to evaporate, for a very long delay. Other consumption tests may involve fire; a candle attached to a lever pushes it down with its weight, but if it is lit, wax lost to melting reduces the candles weight, eventually activating a trigger. A simpler, more iconic method is the candle slowly burning through a rope; when the rope breaks, whatever it is holding up drops.

The speed test generally involves an object falling or rolling a given distance, triggering a lever or pressure plate when it reaches its destination. The mechanism is less complicated in some ways than quantity or consumption tests, and requires less material; a marble dropped into a grooved track is much smaller and will last longer than a barrel of water waiting to be drained. On the other hand, a speed test usually requires more space than the other two tests, especially for long delays. A variation of the speed test involves a waterwheel or windmill that can be connected to a series of gears arranged as a mechanical counting device. Tripping one trigger engages the power source to the gears; every time the first gear completes a revolution, it advances the second gear one increment, and when the second gear completes its revolution, it increments the third, and so on; this allows for more precise delays, but obviously involves more planning. And similar to the quantity test, the wheels can be set to advance every time an event occurs, instead of continuously after a single event, so that a trap can be set to go off after every 12 pulls of a lever.

The mechanism of any delay counts as a separate item that can be searched for, in addition to the trigger that activates the delay or the final trap triggered by the whole system. They are usually hidden inside wall or ceilings, or below floors, making them hard to see, plus the adventurers may notice an initial pressure plate and assume everything is safe when it is triggered from a distance, but appears to have no effect. There may be other clues to the mechanism's presence; water draining from a barrel may spill a little and seep through cracks, while a burning rope may give off an odor. Also, there may be a slight noise from water or sand falling, or quite a bit more noise from wheels squeaking as a stone weight tied to a rope descends, or a marble rolles down a series of ramps.

Traps: The Equilibrium Trigger

An equilibrium or balance trigger is a balanced plate with lever, spring, or compression triggers near two or more edges, instead of in the center. If an object is placed directly in the center or lifted straight up, the trigger isn't activated; if an object moves from the center or lands on an edge, the trigger is set off.

This has several potential uses, the most obvious being a platform for a treasure chest. Inhabitants can remove the chest without disabling the trap by lifting it straight up; adventurers are more likely to push or drag the chest, shifting the plate and setting off the trigger.

A variation of this is to make an entire section of floor into a large equilibrium trigger. If the plate is large enough, even moving a few feet from the center might not set it off, at least not right away; trying to reach the door, on the other hand, activates the trigger. Dwarves will be able to notice the slight slope as the floor tilts; others might not notice until the the tilt is enough to activate a lever. Options for this would be to drop a party in the center of a room via a chute or to have a large hidden catch or support under the floor in front of one entrance, so that adventurers can reach the center but not an exit on the opposite side. Avoiding this might involve jumping to the center of a room, then to the doorway, assuming the door is open.

One gimmick that pressure triggers and compression triggers don't share is that each tilt direction can have its own, separate mechanism, which means different traps can be triggered depending on which direction an object moves across the balanced platform. A floor with a balanced platform might trigger portcullis traps for individual doorways, based on the direction an adventurer is moving towards.

Equilibrium triggers are detected in the same way as pressure and compression triggers. Methods to disable them, aside from jumping over or into the middle of floor triggers, involve using multiple objects to keep the platform balanced; for example, if adventurers notice a floor beginning to tilt, they can split up and move to separate corners in an attempt to escape the trap. If the ceiling above a trigger is low enough, two or more braces can be used to prevent the plate from tilting.

Traps: The Pressure Trigger

Pressure triggers are similar in concept to compression triggers; in fact, pressure triggers can be based on a bellows compression trigger, although they can also be based on levers. They detect a change in pressure, at which point the trigger is activated, creating a change in a linked object (releasing a catch, firing a crossbow, or producing some other result.)

The simple lever pressure triggers involve a plate or piston adjacent to a lever. When pressure is added, for example by being stepped on, the plate moves the lever, triggering another action. Placing a spring between one end of a lever and a surface that it moves towards when activated means that the lever will return to its original position after pressure is released; this can also be done by attaching a spiral spring in its relaxed state to one end of the lever and the fixed surface it is closest to, so that when triggered, the spring will be stretched, snapping back when the pressure changes. One use for this is a repeating pressure plate which automatically resets when the trigger is no longer activated. Another use is for pressure plates that detect the removal of weight (the idol that triggers a trap when removed from the pedestal.)

A hydraulic pressure trigger uses a fluid that can't be compressed, like water, to transfer pressure from one pressure plate or piston to another. A pipe or channel of any shape or length is filled with water and a loose plug is placed in either end. Pressing one plug in causes the water to push the second plug out, and vice versa. If there is a lever or spring trigger in contact with one plug, the movement of the plug will move the trigger. This is a great, simple way to transfer one trigger effect to another location, especially if a rope and pulley system would be too complicated.

Another use of the hydraulic pressure trigger is to leave one end uncapped, so that the fluid is squirted out of its tube, perhaps creating a slick area or squirting flammable liquid into an open flame. However, this use is perhaps closer in form to a pure compression trigger, instead of a pressure trigger.

Either kind of pressure trigger can have horizontal plates or pistons instead of vertical ones, creating a simple button. This is mostly of use to trigger secret doors, puzzle locks, or to disengage another trigger, disabling a trap.

Pressure triggers are detectable in the same way that compression triggers are: visible difference in coloration or texture between the plate and the surrounding floor or wall, gaps around the plate, plate protrudes slightly, or is recessed slightly into the surface. Tapping a pressure plate may detect a hollow area, but you might not want to tap it, if it is very sensitive. If the mechanism behind the surface is large, the hollow area may be larger than the plate, which means the hollow is detectable by tapping around the plate. A hydraulic trigger might have some leakage, plus the pipe or tube system might be traceable by careful tapping.

Pressure triggers are hard to jam, although it might be possible. The usual procedure is to avoid them or deliberately use a pole or rolling object to trigger them from a distance, although the latter doesn't do much good if it's a repeating pressure trigger. If the trigger detects the removal of pressure instead of an increase in pressure, another object of the correct weight may keep the trigger from activating.

Traps: The Lever Trigger

Lever triggers are pretty common; most tripwires, for example, are connected to levers of some kind, and trapped doors usually involve the door moving a lever. The class of lever, as it turns out, is not usually all that important, although levers that act as compression triggers will probably be Class 2 levers*. What's actually important is what the lever does.

*Since lever classes aren't all that important, I'm not going to define them; see Wikipedia or some other source if you'd like more information.

There are three main jobs a lever can do as a trigger: block, yank, or tap. A catch blocks another object from moving until more pressure is applied. For example, a trap door in the floor might have a catch keeping it closed until it is pulled open by a wire being tugged, or until it gives way under too much weight. Or the catch is normally open, but another trigger pulls it closed, blocking a door. You could, for example, have a hefty metal bar on an axle next to a door; if one end of the bar is pulled away from the door, the bar turns so that the other end blocks the door, keeping it from opening all the way. Place this bar and axle assembly above a door and attach a chain to one end that runs through pulleys, connecting to a trigger on the other side of the door, and you have an entrance that can be sealed after a room is entered. This can be circumvented by not allowing the door to close, or not allowing the bar to turn, perhaps with the use of spikes.

A tripwire yanks another trigger or an object when the lever is moved, or the lever does the yanking; the wire itself is really just an extension of one end of the lever, or acts as a lever itself. One example is a lever mounted on a door frame so that opening the door moves the lever, yanking a wire. The direction the wire is yanked depends on how the lever is mounted (fulcrum in the middle, fulcrum on one end) and where the wire is connected. The tripwire can run across the ceiling of the room where it is located to trigger something else (pull the trigger on a crossbow, for example,) or it can run through a hole in the wall and across the ceiling of the corridor on the other side of the door, perhaps triggering a trap behind the adventurers opening the door. If one end of lever is flush with the door and a spring under tension keeps it pressed against the door, the lever can even be on the side opposite the direction the door opens, which makes tripwires on doors very versatile.

As an aside: Richard brought up in a comment the idea of traps that haven't been "plumbed in", in other words were added after the original construction was finished. Unless the inhabitants have only moved in recently, though, or are loathe to do construction themselves, the main guts of a trap can always be hidden with false ceilings, walls, and floors, which create instant ducts and chambers for tripwires and gears; a dwarf will automatically detect this new construction. There needs to be some kind of opening (perhaps shuttered) for the deployment of the "payload", and the other end of the trigger or series of triggers needs to be exposed or connected to something that is exposed, so that adventurers can trigger it. The tripwire and spring combo mentioned above can be hidden quite well, unlike some of the other triggers mentioned in the series so far; carve a hole in the frame of a door or lip of a container so that the door or lid covers the hole, then place the lever and spring in the hole, so that opening the door or lid allows the spring to push the lever out, triggering the trap. This kind of trigger would be very difficult to detect, so use it sparingly, unless you want to provoke player outrage.

A hammer trigger hits or touches another object when the lever is moved. Levers used as compression triggers to break some object would be one example, but the intention can be something else entirely; for example, a hammer trigger could strike a bell, to act as an alarm, or it can push a bar in a groove, to bar a door. The giant electric switches in old mad scientist films are another example; moving the lever causes the metal part to touch a metal plate, completing an electric circuit. Going back to more violent uses, a hammer striking an object can be another method of launching a projectile; perhaps a trigger on a door is linked to multiple hammer triggers in the form of mounted croquet mallets, which hit balls across the room to create obstacles to trip over.

Lever triggers are visible if an adventurer can see the location where the trigger is located. Levers on the other sides of doors can't be seen without magic, of course, but sliding a blade between a door and its frame might contact the lever, and might even reveal a hollow in the frame itself. Disabling levers generally involves wedging something in between the lever and the direction it moves towards; the iron spike can be your friend, here, as it could even disable the hidden spring and lever trap mentioned earlier. If a lever moves something else through some kind of channel or groove, the channel itself can be blocked.

Traps: The Compression Trigger

A compression trigger is related to pressure triggers and equilibrium triggers, which I will be describing soon. I almost called it a "crush trigger", but I thought people might misinterpret that as a crushing walls trap. This is a trigger: compressing or even breaking an object, such as by walking over it, triggers a result. There are two basic types, based on whether the trigger breaks or compresses an object or is itself broken or compressed.

The first type is the fragile compression trigger or "breakaway" trigger. The most basic example is a pit trap covered with a weakened platform or lid, such as balsa wood or glass, which won't support any additional weight (this is distinct from a trap door, which will support weight, but is held in place by a catch which can be opened by a trigger.) Breakaway triggers are usually pretty obvious visually, although sometimes, the floor and the platform are covered with sand, mud, pebbles, or some other substance to hide the exact location; in this case, there is an obvious visual clue that a trigger is present, but another method (such as tapping to locate hollow spots.) Variants involve something that breaks on contact that is not necessarily a platform, such as a weak support column that will break if hit by a door that's been kicked open, causing the ceiling to collapse.

The second type is an indirect compression trigger. A simple example is a loose flagstone placed on top of one or more fragile containers (glass, thin bladder, pottery, or a gourd.) Stepping on the flagstone crushes the containers, releasing their contents, which could be poisonous gas, or chemicals that catch fire when mixed with each other or when exposed to air. For the door variant, a glass flask or other fragile container could be attached to the other side of the door, so that if it slams against something, the contents are released.

Instead of a solid surface, it's possible to use sand, mud, snow, or another substance which compresses under weight. This can be a variant of the breakaway trigger, or the substance can cover a fragile container as above. This is essentially a primitive equivalent to a landmine. Inhabitants of a lair may place multiple "mines" in a room, leaving a path only they would know so that they could pass safely. If multiple adventurers cross such a room one by one using the exact same path, the first person would definitely trigger a "mine", but the second person would have a slim chance to miss any remaining mines; each time a mine is triggered along the same path, the chance improves a little bit more for anyone taking the same path, as the triggers are slowly used up. If the contents of the container leave a "stain" in the sand, mud or snow, or if victims bleed when affected, this could leave a visual clue to the danger.

Not all compression triggers involve breakage. Consider a bellows or a sturdy bladder with a valve; stepping on a flagstone compresses the bellows or bladder, forcing air or some other fluid out, perhaps through a pipe. One simple use for this is to have some kind of fine, powdery poison or dust in the tube, blowing it up into the air around the person stepping on the trap. This could cause coughing, blindness, suffocation, or some kind of toxic reaction. Similarly, a needle or dart could be loaded in the tube to be fired when the bellows is compressed. The more common use for this variant is to use the air stream to trigger something else; this can be one form of pressure trigger, for example. The benefit of a bellows trigger is that it's repeatable, as long as it's not linked to another trigger that has to be manually reset or reloaded. You could design a stack of needles that drop into a tube one at a time, with the tube connected to a bellows trigger, to get a repeating needle trap.

There's not much that can be done to disable a compression trigger. Usually, you would just avoid it, or attempt to trigger it from a distance (rolling barrels or boulders over sandy floors, for example.) Compression triggers linked to doors that are opened too far or too violently are hard to detect and thus hard to avoid, but if adventurers can peer through a crack in the door or the keyhole, or otherwise find some way to see what's on the other side of the door, they may have enough warning to try opening the door carefully. For a bellows trigger, adventurers can locate the tube to cut it or otherwise block it, which would actually disarm the trigger.

Traps: Shutters and Valves

I hadn't planned on doing shutters and valves next, since they are almost always activated by other triggers, like levers. But I've already mentioned shutters in the previous post, and they're a fairly simple topic, anyways (no need for an illustration, either;) so, I might as well tackle them now.

I'm using the term "shutter" to mean an obstruction that blocks a hole; a valve usually has a more complicated structure, but it does basically the same thing. The most common shutter, of course, is a door or lid; when closed, it can not only block access or vision, but it can also prevent the release of tension in spring triggers, as we've already seen. Another trigger can be used to open a shutter, releasing dangerous substances. Consider this: subterranean dwellers discover a large underground vent of deadly gas; they carve a channel or construct a pipe through rock to direct the gas to a particular area, then cover the vents with shutters, opened by another trigger. A similar concept is to use a shutter as a floodgate; opening the floodgate dumps water (or sand or boiling oil.)

Shutters can be left open by default instead, with a mechanism to close them when triggered. This is your basic portcullis trap: the gate is raised by default with a catch to keep it in position, with a trigger to release the catch, dropping the gate and preventing access.

Detecting shutters is usually pretty easy visually, except in darkness. Tapping on the wall should also reveal hollow areas behind shutters. If the shutter blocks release of a gas, liquid, or grainy substance, there will probably be some leakage, either visible or perhaps detectable as an odor. If the shutter is open, either adventurers will see the propped-open shutter, or there will be a hole in the threshold of the route the shutter would block. Disabling a shutter trigger usually involves a wedge to keep it open or a spike to keep it shut.

Traps: The Spring Trigger

I figured I would start with spring triggers. These are not necessarily the spiral-based springs we're all familiar with, but instead are often mere tines of springy material, like steel, which stores energy when it is bent back, releasing it when tension is released.

A basic spring bar makes a very simple trap. A thin, flexible metal, wood or bone bar is embedded in a floor one spear-length from a door that opens away from the bar. The butt of a spear is placed against the bar so that the bar flexes back as the door is closed. The door now maintains tension in the spring; opening the door causes the tension to be released, and the spear is thrust forward. There may also be some form of support between the bar and the spear head, to help keep the spear horizontal and guide it as it is thrust forward; to eliminate this, a menacing spike can be welded to the bar instead of using a spear. The spear or spike targets the person directly in front of the door and can be automatically dodged if the character is not surprised.

This kind of trigger isn't immediately visible unless it's in a lit room; in that case, looking under the door will reveal a shadow cast by the bar, at the very least. If an adventurer can slide a long, thin tool under the door and swish it back and forth, the adventurer can feel an obstacle; however, the tool used must be longer than the spike or weapon (spear, javelin, bolt, dart) used in the trap.

A spring bracket is my made-up name for a smaller version of the same kind of trigger. Unlike the large spring bar trigger, the spring bracket is placed so that the door opens towards the trigger. The bracket is placed near one edge of the door with one tine against the door, under slight tension. As the door is opened, it flexes the tine more and passes it, causing the tine to suddenly release. The tine is usually connected by string or a wire to another trigger, such as a crossbow trigger; triggering the spring bracket yanks the wire and triggers the crossbow.

A spring bracket, like a spring bar, can be detected by sliding a thin object between the door and its jamb, lintel, or sill. However, because it is much smaller and right next to the door, a knife or dagger is usually long enough to reach it.

Although I've described these in terms of a door, the same principal can of course be applied to lids of containers, or the spring bar can be used with some kind of catch which is released by another trigger. It's just that the door traps described are the simplest to visualize. When used to trap a door, usually there are two or three doors heading toward the same direction; one door is safe and untrapped, the other two are trapped and lead nowhere. Those who set the traps know which doors to open and which should remain shut.

When a simple spring bar with a spike on it is used in a chest or any other container, there are more options. Consider this diagram of a chest with a lid that has a rim. If the bar is placed perpendicular to the lid, the spikes can be held in place by the rim and will stab towards the lip of the chest if it is opened only a crack (Arrow A.) If the bar is parallel to the lid, the spikes stab upwards (Arrow B.) This arrangement can be detected if someone opens the lid a crack and slides a knife blade in to swish around, but this method may be dangerous for Type A.

Most other detection techniques will have no effect on these kinds of chest traps, although if a lid looks like a flat slab, but actually has a hollowed-out area to create a rim for a Type A trigger, tapping the lid in several places will detect the hollow area. Normally, an adventurer wouldn't disarm this kind of trap, either, but instead would try to avoid the path of any such trap, for example by standing behind an obstacle, or lifting the lid slightly with a long object.

A spiral spring with a catch can be used to launch a needle or dart in any direction, including through holes in the lid, front or sides, or from a trap located underneath a chest that has legs. Darts and needles have a longer range than a spike that is part of a spring trigger.

I Search For Traps

This post is inspired by my previous post (or, more accurately, the comments from Richard and Brendan,) but it's not actually what I planned for the trap series. The trap series will actually focus on kinds of triggers that seem reasonable for a pseudo-medieval setting, what kind of clues would alert adventurers to them, and what could reasonably be expected from some standard trap detection techniques. I figure I'm perfect for this kind of article, since I have great trouble-shooting experiencing (I worked for two different tech companies,) but I have no special training in traps or engineering, so I'm an ordinary guy who's a natural problem-solver -- exactly like most people, especially those who are typical players, or typical PCs. Consider this post to bonus material for the DVD.

I don't like the idea of a simple skill roll to search for traps, but that doesn't mean I like or use the extreme pixel-bitching approach to traps, either. I'm probably just a little more detailed than Brendan describes for his own technique. If someone says "I search the room", I ask "how", but all I'm expecting is general details: Do you enter the room, or stay outside? If you enter the room, do you just blunder on in, walk normally, or creep along slowly? Are you just searching visually, or are you touching things (with or without a 10-foot pole?) And if you're touching things, are you actually tapping or knocking, or are you moving things around?

So, basically, it breaks down to speed and direction, stance, senses and tools used, and any changes to the environment made. I assume, unless told, that you do everything that could be included in the general description of what you tell me, without going too far. You stand in the doorway and do a visual search? Then anything that *could* be seen from where you are standing is seen, no roll necessary, and no weaseling out by saying "you didn't say you were also looking at the ceiling". I figure that these are the basic search procedures:

• Blundering In: You enter the room without searching. This always applies for those fleeing monsters, unless you say otherwise.
• Careful Entrance: You enter, but not necessarily quickly, and look at stuff as you enter. This action stops as soon as you spot anything out of the ordinary (no roll needed, as long as it's visible and not hidden.)
• Stop, Look and Listen: You don't enter the room, so no traps triggered by movement or pressure will go off. Anything visible or audible -- or smellable, or detectable by any other sense that works over distance -- is automatically detected.
• Cautious Test: You use a ten-foot pole or similar technique to test from a distance. Discovers a few things you'd miss by the previous techniques. If you also add tapping with the pole, you discover hollow spaces as well.
• Thorough Test: You touch what you're searching, everywhere. Discovers hidden catches, buttons, and the like.

All of these assume you are standing up, bending and crouching only as needed, and make no changes (nothing is moved or opened.) A careful entrance assumes you look under things, on top of anything you can see the top of, behind anything you can see behind, and around every corner you can look around. The first time you would notice something out of place or out of the ordinary, I describe that, and assume you stop until you tell me what you do next. If you have to move something or open something to continue a search, I ask if that's what you want to do.

Richard's comment brought up the topic of expectations. What do I lead players to expect, and how do I want them to behave? I think that depends on the general type of location.

• Wilderness has natural dangers that may function like traps, but nothing too devious in most cases. The expectation is that adventurers will proceed carefully and stop, look and listen when discovering something new.
• Inhabited lairs are going to have alarm traps and sentry points, plus a few check points where you have to enter the area in a certain way to avoid injury or capture (like the one-way corridors.) If they have time and resources, there will also be branches where you have to chose the correct path or walk into a trap. The expectation is that adventurers will scout a known inhabited area and try to observe the behavior of the inhabitants. Once scouted, careful entrance would be the norm, with cautious testing of missed areas and treasure containers.
• Ruins and abandoned lairs will have pits, the occasional untriggered lair trap, and some natural hazards from crumbling structures. Untriggered traps would be dealt with as for inhabited lairs, but there's a chance the trap simply doesn't function, due to age.
• Legendary vaults and tombs will be known to have escaped looting, somehow, so this is where the truly devious stuff would be. Adventurers are assumed to have picked up a few rumors about the scary dangerousness (and tempting riches) of such a place beforehand, so the expectation is that this is where the adventurers should be paranoid.

A megadungeon is basically an underground wilderness with individual areas that stand out. Most of the time, the adventurers would worry only about being spotted by dangerous creatures, missing interesting discoveries, or blundering into something obviously different. Within this framework, there will be lairs (inhabited or not) and occasional legendary areas.

Traps and Triggers

There's a thread on Dragonsfoot about using the old school approach to detecting and disabling traps; in other words, having players describe how they search for traps and what they do to disable or avoid triggering the trap. The person who started the thread wasn't sure how to handle this: what possible ways could a player use to search? How do you enable people with no special knowledge of traps in the real world to role-play a knowledgeable character in a fantasy world? What if the player just creates a huge list of actions to search for traps and says "I do all this" every time? I responded in thread mainly to the last point, but it occurred to me that I could do a whole series of posts on the topic, based not on any special knowledge, but just thinking about basic mechanics like levers and pulleys, what they could do, where they could be located, and how they would be noticed.

The important things to remember are:

• A trap has two parts: the trigger and the result.
• Each part must be detected separately, and may require different search methods.
• Search order is important; one method may find a trigger, another method may trigger it.

There are a couple very basic triggers, but these can be chained (the result of Trigger A is the triggering of Trigger B.) They can also work in parallel (a lever in Trigger A moves two other levers simultaneously, triggering Triggers B and C.) Sometimes Trigger A disengages Trigger B, making another action safe, so finding a "trap" and avoiding or disabling it is not always a good thing.

Results can be pretty varied, but they can all be simplified to an action delivered along a particular path, from Origin Point A to Target Point B. A character standing at the target point or along the path between the origin and the target is in danger of being caught in the trap. Examining Point A may locate a trap, but not its trigger; examining Point B may offer clues to what kind of result to expect (scorch marks on a wall are a clue to a flame thrower trap, debris on the floor may be a clue to a deadfall.) Some results, like releasing a gas, might not be obvious from any kind of clue.

When constructing a trap, you should consider both obvious actions (walking over a trapped floor, opening a trapped door) and search methods (touching or moving a trapped chest.) Sometimes, a particular search method will trigger the trap, which might not be a good idea based on whether you are standing in the path of the result or not.