The perception score: a new way of looking at things
by Thomas Ruddick
| Minimum ability scores | Bonuses for high perception | Generating perception scores | Perception in play | - |
| Dragon 133 | - | - | - | Dragon |
His Honor the Lord Mayor was naturally
quite interested in the adventurers who
took temporary residence in one of the
f i n e r i n n s o f t h e
t o w n ? e s p e c i a l l y w h e
n
he learned that one of their aims was to
find the local assassins? guild and settle an
old score with it. The guild had caused the
Lord Mayor many problems in the past,
and he welcomed the possibility that the
g u i l d m i g h t s o o n
s u f f e r p r o b l e m s o f i t
s
own. The adventurers, however, were
close-mouthed and were cool toward his
offers of assistance.
H i s c o u r s e o f a c t
i o n w a s t o r e l y
o n t h e
capable services of Ferd, his halfling
informant. Ferd began to tail the adventurers whenever they ventured
into the city
reporting back to the Mayor on their
a c t i v i t i e s .
A t t h i s p o i n t , t h e
D M c r e a t i n g t h i s s c e n
a r i o m u s t p a u s e . O b v i
o u s l y , t h e g a m e i s
g o i n g t o d e v e l o p i n
d i f f e r e n t w a y s d e p e n d i n g
o n w h e t h e r o r n o t
t h e a d v e n t u r e r s
n o t i c e t h a t a n o n d e
s c r i p t h a l f l i n g i s f o
l l o w-
ing them around. How should he determine if the characters notice or
not?
The official AD&D® game rules
have no
provision for dealing with most situations
like this one. The Players Handbook contains rules
for elves or dwarves
discovering secret doors or pits, and for thieves
detecting traps, but it has nothing that
applies in general to situations in which
characters might or might not notice
something.
Each DM seems to have a slightly different method for dealing with
this sort of
situation. Some roll a die and let players
?roll higher? to 
whether or not a discovery is made. Others simply require the
players to ?roll high? to acquire the information. Some suggest that
the players
make ability checks (as described in
Dungeoneer's
Survival Guide) against intelligence, wisdom, or dexterity. Still
others
never design such ambiguous situations
into their games -- whether the players
notice an unusual event or not is simply
determined in advance But none of these
solutions seems satisfactory. Dealing with
them one at a time:
1. Purely random die rolls assume that
all characters are equally sharp-witted ?
not a very realistic assumption.
2. Saving vs. a character's intelligence,
wisdom, or dexterity score is also unrealistic. Why isn?t it possible
to have an intelligent, wise, or dexterous individual who
also happens to be less than alert much of
the time? Basing this saving throw on
those abilities seems about as appropriate
as making a bend bars/lift gates roll on the
basis of charisma ? the ability score was
not designed to include this attribute.
3. Restricting game design to exclude
these situations takes the interaction out
of the game. In advance, we know if the
party will obtain information or not, so
the game becomes more of a story told by
the DM, with players? actions and characters? abilities having less
effect on the
outcome.
The RUNEQUEST® game has a character
ability score called Spot Hidden, which
covers the detection of anomalous situations and objects. The closest
thing the
AD&D game has to this is the surprise
roll,
but this applies most strongly to combat
situations with living foes. So far, no official AD&D
game rules have been published to deal with ?general detection?
powers, so individual DMs and game
designers have had to come up with individual ways of coping with this
shortcoming. As a result, different games still lack
consistency in this area. We need new
rules that would provide general guidelines for all of these possibilities.
<BEGIN READING HERE>
My own solution has been to create an
eighth character ability score: perception.
It is similar to the original six ability scores
for strength, intelligence, wisdom, dexterity, constitution, and charisma,
each of
which is normally a number from 3-18
used to describe a range of related abilities
that an AD&D game character might
possess.
Perception describes the quality of a
character's vision and hearing, as well as
mental habits such as attentivtiness, visual
and aural memory, and interest in his
surroundings. Perception is important to
all character classes, as it affects the character?s chances to notice
things that might
be important in the course of the game
(and not merely surprise in combat).
Normally, a character?s perception score
is between 3 and 18. However, a character
with a perception of 3 or 4 would suffer
from severe vision or hearing impairments
? such a character should probably be an
NPC, since he probably would not last long
as an adventurer. (Survival is unlikely
when the character has a hard time seeing
or hearing whatever is attacking!) A character with a perception score
of 9-11
would have normal (20/20) vision, hearing,
and habits of observation. Characters with
scores above 15 would be exceptionally
observant individuals, gifted with particularly sharp eyes and keen
ears, and being
habitually attentive.
M o s t c h a r a c t e r s s h o u l d
b e a b l e t o s u r v i v e
w i t h a v e r a g e o r e v e n
l o w s c o r e s i n
p e r c e p t i o n , a s s u m i n g t h e
y c o u l d c o m p e n s a t e w i
t h o t h e r a b i l i t i e s o r
b y d e p e n d i n g
o n o t h e r c h a r a c t e r s .
A f e w c h a r a c t e r
c l a s s e s , h o w e v e r , r e q u i r
e a b o v e - a v e r a g e
p e r c e p t i o n s c o r e s . F o r
e x a m p l e , t h i e v e s
e x c e l a t h e a r i n g n o
i s e s ; r a n g e r s c a n f i n
d
t r a c k s t h a t a r e n o t
a p p a r e n t t o o t h e r s ;
a s s a s s i n s a n d n i n j a s
a r e s k i l l e d a t d i s g u i
s e
a n d c o u n t e r f e i t i n g . E a c h
o f t h e s e a c t i v i t i e s
r e q u i r e s h i g h l y d e v e l o p e
d p o w e r s o f p e r c e p t i o
n . T h e r e f o r e , i t i s
a p p r o p r i a t e t o s e t
m i n i m u m p e r c e p t i o n s c o r e
s f o r t h e s e
c h a r a c t e r c l a s s e s .
D o i n g s o g i v e s e v e n
m o r e l e g i t i m a c y t o
p e r c e p t i o n a s a c h a
r a c t e r a b i l i t y ? a l l
o f
t h e o t h e r a b i l i t i e s
e x c e p t c o m e l i n e s s t a k e
t u r n s a s r e q u i s i t e
a b i l i t i e s f o r s e v e r a l
c l a s s e s . A l s o , s u c h
a n a t t r i b u t e a d d i t i o n
f o r c e s p l a y e r s t o m
a k e t h e c h o i c e b e t w e e
n
d i f f e r e n t t y p e s o f
c h a r a c t e r a b i l i t i e s . F o r
e x a m p l e , a p l a y e r w
h o r o l l s m o d e r a t e l y
w e l l u n d e r t h e e s t a
b l i s h e d r u l e s m i g h t
c h o o s e t o p l a y a
r a n g e r i n s t e a d o f a
f i g h t e r , b e c a u s e t h e
r a n g e r c a n f i g h t j u s t
a s
w e l l a s t h e f i g h t e r
a n d g e t s m o r e h i t
p o i n t s
a t t h e o u t s e t ; f u r t
h e r m o r e , t h e r a n g e r ? s
t r a c k i n g a n d s u r v i v a l
s k i l l s m i g h t h e l p t h e
p a r t y i n u n i q u e s i t
u a t i o n s . B u t i f a
h i g h
p e r c e p t i o n s c o r e i s
r e q u i r e d , t h e n t h e
p l a y e r r e a l i z e s t h a t
t h e r e m u s t b e a
t r a d e o f f b e t w e e n f i g h t i n g
s k i l l s a n d d e t e c t i o n
s k i l l s , a n d t h e f i g
h t e r c l a s s m a y b e c o m e
a n
a t t r a c t i v e o p t i o n f o r
t h e p l a y e r w h o w a n t s
o n l y t o h a c k a n d
s l a s h .
T h e s e g u i d e l i n e s a r e
f o r o f f i c i a l c h a r a c t e r
c l a s s e s o n l y , b u t g a m
e r s w h o u s e a
d d i t i o n a l c h a r a c t e r c l a s s e
s ( l i k e t h o s e t h a t
a r ei n t r o d u c e d e v e r y s o
o f t e n i n D R A G O N
®
M a g a z i n e ) s h o u l d b e
a b l e t o a d a p t t h i s
i n f o r m a t i o n e a s i l y e n o u g
h . K e e p i n m i n d
t h a t a p e r c e p t i o n s
c o r e o f 9 - 1 1 i s
a v e r a g e ,
1 2 - 1 4 i s a b o v e a v e r
a g e , a n d 1 5 o r o
v e r i s
e x c e p t i o n a l .
R a n g e r a n d n i n j a .
Minimum perception: 15. Both of these classes depend heavily on
perception. The ranger is skilled at tracking, woodlore, pathfinding,
and spying,
and is surprised only on a roll of 1 on 1d6.
The ninja is also difficult to surprise and is
the most skilled of all the character classes
is disguise. All of these skills demand superior perception; in particular,
the ranger?s
better odds for being surprised must
depend on perception, since the class has
no minimum score for dexterity.
B a r b a r i a n , d r u i d , t h i e f
, a s s a s s i n , t h i e f a c r o b a t ,
a n d y a k u z a .
Minimum perception: 12. Barbarians and druids both
depend on the ability to "tune in" to nature, which would be difficult
without
good perceptual ability. Thieves and
related classes obviously need to notice
things about their intended victims and
potential witnesses, and there is a strong
relationship between perception and many
of their specific skills. Assassins have the
added power of disguise, but their thief-type skills are practiced
at lower levels
than normal thieves use them, so this
balances out.
M o n k a n d b a r d . Minimum
perception: 9.
High perception would benefit either of
these character classes, but their other
minimum scores are already so high that
requiring an above-average perception
would make it almost impossible to roll up
such a character using any fair method.
We can conceive that the monk makes up
for an otherwise average perception by
high dexterity and careful mental discipline; the bard can get through
the mandatory thieves? training period with a
lower-than-normal perception score
because the character can compensate
with experience as a fighter.
Other character classes have no minimum requirements for perception,
but a
character with a perception score lower
than 5 should be severely handicapped as
an adventurer.
Bonuses for high perception
Since characters receive benefits for
having exceptional scores in the other
abilities, the same should be true for perception. On the other hand,
in order to
maintain playability, the bonus system
should be simple. Two sorts of bonuses are
suggested here (one with a complementary
penalty).
First, characters of any class with a
perception of 17 or 18 should receive a
personal bonus of +1 to surprise rolls.
This bonus should not apply to other
members of the party; it simply reflects
the individual?s ability to hear or see things
a split-second earlier than the average
person. This bonus should not apply to
encounters with creatures that are perfectly silent or invisible, depending
on the
situation. This bonus also does not apply
to initiative rolls, since perception is of
limited value when a character is locked in
combat with an opponent. In the same
way, a character with a particularly low
perception would be easier to surprise.
Characters with a perception score of 3 or
4 would receive a personal -1 penalty to
all surprise rolls.
Second, several skills that are related to
certain character classes should receive
bonuses for high perception. The bonuses
for each of these specific skills is +5% for
a perception of 17 and +10% for 18.
These bonuses would apply in addition to
any others. These skills are:
Rangers: tracking
Thieves, assassins, monks: hear noise
and find traps (but with no bonuses to
improve the odds for removing traps)
Barbarian: back protection, detect illusion, detect magic,
and tracking
Ninja: disguise, escape, and find traps
(but not removing them, as above)
Yakuza: hear noise
The bonuses from various perception
scores are presented in the Perception
Score Table.
Perception Score Table
G e n e r a t i n g p e r c
e p t i o n s c o r e s
Generating a perception score should be
easy for existing characters in classes that
require minimum scores for this ability
and for new characters in games that
follow the liberal Method V for generating
ability scores (page 74, Unearthed Arcana).
The same solution works for both of these
problems. If a minimum perception score
is needed, the player gets to roll extra
dice: 6d6 for a minimum score of 9, 7d6
for a minimum of 12, and 8d6 for a minimum of 15. If the three highest
dice in this
roll do not add up to the minimum score
or above, the character automatically
receives the minimum score.
For a character who does not need a
minimum perception score, the player
should simply make one additional roll
with however many 1d6 the DM normally
allows (for Method V, use 4d6). However,
the player should be allowed to reroll any
total score below 5.
Most players and DMs have probably
already thought of dozens of obvious
situations in which an ability check vs.
perception would be appropriate.
* One of the most common situations would be
attacks against the PCs when some members of
the party are sleeping -- the usual
arguments about whether or not a character is
or isn't a light sleeper are avoided
with a simple 1d20 roll against perception.
** Characters who want to search for hidden
items, clues, or persons in a crowd may
also use this 1d20 perception roll.
*** Characters should likewise be given some odds
for success if searching for secret doors,
traps, and other things even if they have
no previous skill at finding such items; a
1d100 roll vs. perception would probably
be appropriate in most situations.
<Note: With the above
paragraph, it is only fair to factor in the elves' bonus to find secret
doors and/or concealed doors.
As well, it is logical that
some races may have a bonus to find traps (eg. dwarves, gnomes, hobbits,
and half-orcs).
Does a d% check apply to
Listen rolls as well? Sure, but there does need to be supporting data,
racial modifiers, and, how this fits in with the thief ability. - Prespos>
Other possible applications are boundless.
To find the appropriate check in these
situations, the DM must consider the relative difficulty of the act
of perception in
the game. If an average perception is
represented by a score of 10, and if individuals with really bad perception
scores
are logically not going to be adventurers,
then players with characters of average
perception will pass a 1d20 check against
perception slightly more than half the
time. Checks against perception using
2d20 will succeed about one time in four,
while 1d100 checks will succeed only
slightly more than one time in every 10
tries. Also, the DM needs to consider
whether or not the character can appreci-
ate what he has perceived -- which may
involve other ability checks vs. intelligence
or wisdom, as the situation dictates.
Applying perception to the example that
started this article, we get this conclusion:
Whenever several members of the party
venture out together, the DM instructs the
players whose characters are along to roll
percentile dice -- the odds that any of
them notice the halfling are slight, so a 1
in 10 chance is appropriate. In fact, in the
course of tailing the party many different
times, Ferd is noticed by two of the adventurers, each on different
occasions.
However, just noticing Ferd once is not
enough -- there is no reason to suspect
that he is following the party unless a
party member notices him more than
once. Both party members who succeeded
at the 1d100 checks subsequently fail the
1d20 checks that would have meant they
noticed Ferd on a later occasion -- so
there is no reason to even attempt the
1d20 check vs. their intelligence scores to
suspect the halfling is a spy.
Unable to locate the headquarters of the
assassins' guild, the frustrated party goes
on to other adventures. In the future, the
PCs may return to the city and try again ?
at which point, there is still a slight chance
that one of them might notice and begin to
wonder about that halfling that keeps
following wherever they go. . . .