Excerpts from “The Construction of
Traps,” by Gramme Stonewerk, Guild of
Security Devices:

The first thing to do when designing a
trap is to consider the client who ordered
it. All traps should reflect the client?s
needs and sensibilities. A generally amiable
wizard who has a reputation for living
on the edge of bankruptcy is not going to
have the same sort of security problems as
the high vizier of some rich, desert kingdom.
Likewise, the wealthy vizier can get
away with having devices that can rend
flesh, though some other person?s sensibilities
would be offended by finding a diced
thief in his halls.

Traps come in two general types. There
are passive or latent traps, and there are
active traps. Passive traps are simple in
design (with few or no moving parts) and
require virtually no maintenance once set.
They sit and catch all who cross them.
Active traps also wait to be triggered, but
involve a complex series of operations
designed to catch or slay the ones who
triggered them (i.e., many moving parts).
Active traps are often selective, only catching
those who fail to disarm them. Regular
maintenance (like reloading) must be made
on active traps, which points out that the
difference between these two trap types is
not only a matter of complexity, but also a
matter of expense and efficiency. Active
traps are both more expensive and more
efficient, while passive traps remain the
favorite of the severely budgeted client.

A recommendation must be made before
proceeding. If you can afford the time,
read the excellent paper by my colleague
Denri Raithe, "Legal Advice For Security
Experts,? when consulting with your client
for the initial plans. Denri makes an excellent
case for getting contracts and money
before starting work. Denri also mentions
the serious problem involving those clients
who seek to keep details of their new
security devices secret by slaying the
maker of the traps. Some traps mentioned
in this article were emplaced for such
clients. A wise trapmaker sends the plans
of his work to at least one friend.

The passive approach
Passive traps may be categorized into
3 subgroups: arresting, fatal, and
magical. Mischievous traps (designed to
confuse or annoy thieves, rather than
capture or harm them) may be considered
a fourth category, though these traps
generally fall under one of the other three
categories, and some mischievous traps
are active ones.

Arresting traps are those that capture
but do not actually do a great deal of
physical damage to those who have
tripped them. These are in great favor
with religious figures and a number of
merchants. (After all, your typical storefront
merchant doesn?t care to have a
great deal of blood strewn about in her
shop!) An example of a passive/arresting
trap is the ?swivel step." Putting pressure
on this piece of floor reveals that it is
hinged like a trapdoor with a simple
spring mechanism. When the swivel step
is tripped, it snaps up into place like a sort
of mousetrap, and the plank suddenly
closes around the trespasser?s ankle. Getting
free is relatively simple, but can be
awkward and time-consuming, particularly
if a locking pin is used.

Fatal traps aren't always fatal, but are
intended to do the maximum amount of
damage to the trespasser. Often, in the
case of passive traps, this is simply an
arresting trap with the addition of a
wounding mechanism: instead of a simple
pit, for instance, a pit with spikes jutting
up from the floor might be used. The pit
may be covered by a trapdoor that swings
open when stepped upon, then swings
shut again using springs.

Magical traps are either fatal or arresting,
but always have a magical component.
The simplest form of this in a passive trap
is the placement of an illusory floor over a
pit. The trapmaker is encouraged to make
use of available spell-casters when possible.
If the client is a spell-caster, so much
the better, since the client then saves a bit
of money by casting the spell himself
while gaining a more useful trap.

The trapmaker is encouraged to make
passive security devices utilizing mindless,
static, long-lived monsters (if the building
codes allow). One device, which was built
for a king who wishes to remain anonymous,
sweeps characters into a pit which
leads to a garbage-disposal chamber,
wherein lies a gelatinous cube.

Passive traps which make use of existing
resources are the most cost-effective and
often the best for word-of-mouth publicity.
After hearing about the above-mentioned
trap, another well-to-do potentate immediately
requested his own trap -- in this
case, one that dropped thieves into a nearfreezing,
underground river situated
beneath his castle.

The active angle
Active traps usually come in 3 basic
types: biological, mechanical, and magical.
Biological traps use animals or plants as a
vital part of their mechanisms. For example,
a biological trap may use a green slime
positioned above the trip mechanism so
that the slime is dislodged and falls on
those passing beneath. This example of an
active trap differs from the gelatinous cube
trap noted above because it must be
reloaded after each use, and a series of
mechanical devices are employed which
could be disarmed by the trap?s owner or
a sophisticated thief.

Sentient creatures rarely have the
patience or inclination to sit around waiting
for the occasional morsel, so simple
plants or animals are often utilized in
traps like these. Plants are, in fact, preferred;
they require little upkeep and care,
rarely make a mess, and are unlikely to
consider a bribe. Even creatures famed for
their savagery can be bribed (throw a
guard dog a haunch of beef and see what
happens). If the animal is a vital part of a
security setup, this may cause an irreparable
breech in security.

Mechanical traps need little explanation;
they are the ones the common man thinks
of when the word ?trap? is mentioned. A
spring-loaded mousetrap, a crossbow with
a string connecting its trigger to a doorway,
and a scimitar blade that slashes out when
a chest is opened are all active mechanical
traps using simple (though effective) mechanisms
which must be reloaded or reset
after each use or series of uses. Absurdly
complex mechanical traps, while famous
among commoners and daunting to
thieves, are rarely worth their expense
and upkeep costs. The KISS maxim (Keep
It Simple, Stupid!) is of critical importance.

Magical active traps are rarely seen but
are very hard for magically unsophisticated
thieves to neutralize. A ?magic
mouth? spell that screams when an item is
picked up, drawing guards and onlookers,
is such a trap, though not an immediately
fatal one. A magical trap that generates a
shock to a thief trying to pick a lock is
another such trap, though the shock effect
can be made permanent by a powerful
wizard. Glyphs, symbols, alarms, and
other magical traps fall into this category
as well. Most of them have either limited
durations or have limited ?ammunition,?
requiring regular upkeep by a spell-caster
(whose services may be hard to acquire,
unless the trap?s owner is one such).

A few words about a fourth kind of
active trap: poisoned ones. Used in combination
with mechanical traps, these can be
extremely deadly, but the services of an
assassin or an alchemist are nearly always
required for emplacement and regular
maintenance. Only the most experienced
trapmakers should even consider the
creation of such devices, and the gravest
caution should be used at all times.

Triggering devices
Triggering devices are of many sorts and
are left mainly to the ingenuity and natural
ability of the trapmaker. However, as
the basic thrust of this tome is to inform
the novice, a few examples are given.

One triggering device is the common
tripwire. Although it may be noticed easily
(as is often pointed out), the wire may
require cutting to be triggered -- a nasty
shock! Tripwires unconnected to traps
may be placed simply to slow intruders
down. Tripwires are effective in darkness,
on stairways, near pits, and in combination
with mechanical devices as part of
active traps.

A second triggering device is the weighted
lever. The lever is depressed when
weight is placed on it, as when someone
steps on a particular flagstone; the other
end rises and triggers the trap. Many
corridor-emplaced triggers are of the lever
variety, setting off anything from ceiling
deadfalls to spear-hurling ballistas. Too
little weight on the lever may fail to trigger
the trap, however; too much weight
may break it.

A third triggering device is the scales.
Here, a weight must be removed from a
pedestal or similar object, causing a mechanism
to move up and trigger the trap. A
wonderful active trap is spoken of in a
certain temple, wherein the removal of a
golden idols head causes the fall of a huge
rolling stone on the incautious thief who
triggers it.

A fourth and simple triggering device is
the flawed support, such as the boards on
a bridge that give out when weight is put
on them. Other examples abound, some of
which are not crafted by the trapmaker.
This is one of the areas where nature,
through erosion and wear, frequently
outdoes humble security workers such as
myself.

Simple trap releases can be further
complicated and put to use in the form of
hollow statues, such as those flanking a
door or actually made a part of the doorframe.
Ceramic serpents, for their long,
coiled shapes, are a favorite for filling with
sand as part of a weighted lever release
with a time-delay. In an emergency
retreat, the owner simply strikes the head
off one of these serpents (allowing sand to
spill out), and flees ahead of a series of
falling metal portcullises triggered in turn
by the descending serpent-lever, or down
an escape tunnel with a door that slowly
grinds shut. Many clients delight in such
creations, which are of great use in case of
revolution, invasion, or murder attempts
? though woe to he who stumbles while
the time-delay is running! Perhaps the
thrill of beating the trap's activation adds
to this trigger?s appeal.

There is also the use of pressure plates.
Consider a locking mechanism concealed
in the bannister of a stair. Stepping on the
topmost step without engaging the lock
breaks a hidden bottle of oil, which then
sprays out along the lower steps. If
strikers (little pieces of flint) are used in
conjunction with this trap, the spray of
flame is considerably more effective.

Other considerations
The use of relatively simple mechanisms
should not detract from the complexities
of a trap. The use of springs, cantilevers,
hinged brackets, pulleys, and hoists should
not be overdone, however. There is a
simple enough problem -- that of making
a trap too complex -- that often fouls up
the trapmaker in the process of the trap's
construction.

As an example, consider poor Alrik the
Lame. His trap for one king included
spikes springing out from ceiling, floor,
and all four walls. Two of the walls then
slowly moved to meet in the center. Unfortunately,
Alrik did not figure out what
would occur when the walls hit that first
row of floor spikes. The walls, of course,
jammed on that row and ceased moving
until long after the trespassers had moved
on. Furthermore, since the trap was powered
by water pressure, 2 of the walls
burst and caused extensive flooding in the
king's dungeons -- and Alrik the Swift
went to the torturers for his name change.

Most traps should have at least one way
of being disarmed or circumvented to
allow safe passage. This is a precautionary
measure for the client's own protection,
and a hedge against such things being
used against the trapmaker. A locking pin
which slides into place as long as pressure
is kept against a certain place is the most
common example. Some active traps have
no means to block their mechanisms; some
people might question the use of these
traps, but they do have their time and
place (for example, in traps leading to a
highly prized treasure cache). An especially
skilled thief might get through any trap
that you can devise; getting to the treasure,
however, is only half the battle. A
panicked guard, running among traps
lying about sprung or ready to spring,
makes a recipe for disaster in cases where
a client considers an item too costly to be
insufficiently safeguarded. Guards are not
as easy to replace as some think!

Some traps may remove the object
guarded rather than removing the thief
seeking it, even to the extent of destroying
the protected item. Obviously, the client
might not desire this latter alternative.
Consider a tray of gems trapped in such a
way that the tray slips back into a
recessed chute, which slides back and
away to a sealed room on the floor below.

On this note, consider the case of
Salovar the Restless, a thief of great skill
but doomed to existence as a vampire. The
typical spiked walls, snares, and alarms
did not deter him, but Salovar hadn?t
reckoned with the simplest precaution. In
making his way to the trophy room of the
Earl of Freglass, he found the central case
and removed the sceptre within. The
sceptre, of course, was a fake ? a good
and expensive one, but less costly than the
real thing. A lacquered piece of wood on
the case had to be moved to reveal the real
sceptre, which was less than a foot below
the phony.

Thus, removing the object sought by a
thief may be easier than trapping the thief
himself. To be sure, when the thief is of
average ability, he can be killed by normal
means or at least imprisoned. Cases such
as that of Salovar the Restless are rare, but
they do happen; a trapmaker needs to
consider these things when designing
security measures. Some of the triggering
mechanisms may rely on pressure, but a
leprechaun might pass through these with
little trouble. Considerations of what a
trap won?t catch must be made in advance
of a security system?s design.

Remember: A trapmaker doesn?t just
build traps! The true trapmaker designs a
complete, customized security system.
Rather than relying on one or two traps, a
layered system is strongly suggested.
Indeed, a human thief traveling deep into
a layered security system may find strange
odors and liquids that seem both absurd
and useless ? substances that repel xorn
or nauseate vampires. Holy water, garlic,
and other reagents are effective against
many creatures. A thin layer of silver on a
weapon?s edge adds a great deal to its
efficiency against supernatural creatures.
These traps are not reliable on their own,
but as part of a truly comprehensive security
system, they can add immeasurably to
the designer?s reputation.

Conceptual-design notes
As stated before, when designing your
system, consider your client first; consider
not only the client?s moral code, but how
much money he can afford to spend.
There is a saying attributed to the thieves?
guild that applies here: ?Do not kill the
goose that lays golden eggs." To thieves,
this means: ?Don?t take so much that your
target cannot recover if there is a chance
you'll be able to steal from him again." To
trapmakers, this means: "Don't exceed
your client's means where upkeep of the
trap or payment will keep his coffers
drained.? If you keep an eye out for your
client's expenses, the reward will show
itself in increased business.

Now consider the client's line of work. A
king or major warrior always has followers
who can be put on guard detail.
Less likely to have a corps of followers is
the wizard. Priests always have followers,
and these can usually be put into service
as guards. Guards (men, animals, or monsters)
will always be the outer perimeter
of protection.

Inner layers of protection usually call
for the less-accessible regions to be guarded
only by creatures that don't require
frequent food and water. Among some of
the less moral clients, this is usually performed
by undead of one variety or
another. Similar guardians include constructs
such as golems. If your client
wants a treasure cache that can be
accessed frequently, this is a security risk
and you should advise your client accordingly.
Among trapmakers, this is known as
?guarding your backside.?

The client may merely wish to deposit
new treasure in his cache. This is best
done through a series of small slides
which allow for the deposit of wealth
from a distance. The client will probably
wish to view his treasure cache once in a
while; therefore, the making of the security
systems overview (i.e., a map) may be
necessary. Other, cheaper security systems
will guard the map while the bulk of
wealth is in the security system described
by the map. Since there should be guards
(unless the location of the cache is secret),
the ?boss? can get by the first level of
security without difficulty.

An excellent example

Map by Diesel

Since this client has reneged on payment
for his traps, the Grey Griffon Inn in the
town of Phalanx is here given as a sterling
example of a well-designed security setup.
This particular client, an extremely
wealthy robber-baron named Dorobo Red,
is the secret owner of the inn, and his
guards (disguised as bouncers) patrol the
premises. The entry to Dorobo Reds treasure
vault is actually one of the massive
beer kegs built into the basement wall. A
comprehensive display of this system is
shown in the accompanying illustration.

The first beer keg (#l) is trapped; the
other two hold beer and mead. Any
attempt to turn the keg?s nozzle without
first opening the tap results in a thin spray
of poison spurting out. The door can be
opened as soon as the nozzle is turned. At
the back of the keg is a secret door; this is
opened by depressing a small section of
board in the upper righthand corner of
the keg. A small corridor is revealed,
leading to a T branch heading north and
south. The south branch apparently ends
in a door and seems clear of guards --
thanks to the permanent illusion, which is
fairly detailed and hard to detect. Creatures
with a good sense of smell should be
able to penetrate it since the plant at the
far end (E) has a distinctive, musky odor. It
is a fairly large snapper-saw plant, called
by some the forester?s bane. The tiny grill
windows along the ceiling of the corridor
provide sufficient light for the plant to
thrive. These windows are only about the
width of a normal hand, razor-edged, and
frequently checked by the inn?s outdoor
?gardener."

The north path is the one for would-be
treasure-hunters. The first door is not
trapped in any normal manner. Instead,
hanging from a strip fastened on the other
side of the door are many small bells.
Opening the door causes a jingling noise,
but other than surprise, produces no
other reaction or effect. The noise generated
by these is insufficient to arouse
anyone further than 30? away, but may
cause fear and confusion among thieves.

The guardroom (F) is equipped with a
small cistern, cot, chair, and some supplies.
When an alert is on, one of the more
powerful guards is posted here. Also
found here is a large gong with a mallet
tied to a peg. If the gong is rung, the entire
inn is aroused. (Many recurring ?guests?
are in the employ of the robber-baron.)
Also found here are two doors. The north
door leads to a small utility closet; the
other leads to another short corridor to
the east.

The short corridor (G) has a pit trap
with a mechanical door. Should someone
walk into the corridor without first closing
the door leading to the guardroom, the pittrap
door is unlocked and free to swing
open, dropping the thief 30? onto many
sharpened metal stakes.

Beyond the pit-trap corridor is a small
metal door, about 3? in height. The corridor
beyond is also 3? in height. This is a
security measure, since if a human is
trying to walk out with a great deal of the
treasure, it will take him some time to
navigate the passage while hauling a load.
Immediately beyond the passageway is a
trench (H). This is 40? deep and runs the
length of the room. The ceiling is still only
3? above the floor at this point making
jumping difficult. At the far side of the
trench is a crank (I) which causes a small
bridge to stretch across the abyss. Since
both the owner and one of his chief
henchmen know a spell to summon an
invisible servitor, a tiny ledge has been
built around the north end of the trench.
The magical servitor, once summoned and
sent across the trench, can negotiate this
path, then lower the bridge into place.

The corridor then opens up to a normalsized
passageway. A single brass-bound
door is set here, with a relief image of a
roaring lion upon it. If the door is
unlocked and opened, it reveals a wondrous
device called a ?mirror of opposition
? affixed to a second door immediately
behind the first. If one feels inside the
lion?s mouth before opening the first door,
he will find the true doorlatch which
cannot be locked from either side. The
second door then opens with the first one.

Beyond this point is a room (J) that holds
the greatest treasures from Dorobo?s raids.
This room is known to house several magical
weapons and gemstones, spell books
from great but deceased wizards, and
various potions in addition to heaps of
coinage. This trap setup is used purely as
an example of a reasonably solid security
system, and it is my hope that it provides
food for thought for all who are interested
in the subject of traps and those who use
them.

And remember -- pay your bills.