~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ P E R C E P T I O N An Optional Statistic ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Date: 12 February 1997 WRITTEN BY XENO (mlsheltn@cc.memphis.edu) >> A BIT OF INTRODUCTION This Netbook was written in response to James Duerr's inquiry in the "rec.games.frp.adnd" newsgroup about rules on the use of vision. With this impetus, I began designing a table or two, then wandering into the hearing category, and made more tables, and realized things like THAC0 and thieving skills can be affected, and only then realized how broad a scope Perception would encompass. Eventually the result is this Netbook you are reading. It has been redone to ensure at least some semblance of scientific accuracy, with the good and much - needed advice of Steven C and Jason Burzenski. WHAT IS PERCEPTION? Perception (PER) is an aggregate of vision and hearing, and to a lesser extent touch, taste, and smell. Research has shown that were one sense disabled, the other senses would be enhanced to make up for the loss. Thus if a character is blind and his PER is 10, then this shows that he has exception hearing which has compensated for his blindness. If he was deaf then the reverse is true, or else another sense has "enhanced" itself to compensate for the missing sense. Thus Perception has been purposefully made to resemble, but not mimic the subability rules found the Player's Option: Skills & Powers book. There exists in the Guinness Book of World Records a case of a woman who can see twenty times better than any human. She can identify faces from a mile away, and was able to notice that a piece of thread was really four threadlets twisted together. While one cannot begin to "picture" having vision this acute this gives you some idea of the possibilities of keen human senses. Perception is, first and foremost, a tool available to a DM to resort to a dice roll instead of having to arbitrarily decide whether a character has heard a noise or can taste something in the food or whatnot. It can also give characters more variety in usefulness and role playing -- that wimpy thief who has little talent otherwise may be invaluable to being able to see the enemy at much greater distance than any of his pals. A dwarf or gnome with very good taste buds might be employed at a high wage as a food/wine taster for nobility, because of their poison resistance. One might imagine a blind fighter that fights just as easily in complete blackness as he can in broad daylight because of his adeptness at blind - fighting. There are a vast number of possibilities! DETERMINATION OF PERCEPTION SCORES. All PCs, NPCs, and monsters which do not have an explicit PER score are assumed to have a PER of 10 - 11, unless the DM deems that the character or creature should have another level of Perception. This would include birds of prey, bloodhounds, and dragons, for example). For all intensive purposes deities, demigods, and avatars should be treated as having a PER of 19. It also seems reasonable that Elementals would have a PER of 19 when detecting their native element. For demihumans and humanoids, PER is determined by rolling 3d6. Some races are given PER modifiers. A chart of Racial Minimums and Maximums for the demihuman races is given below. RACE MIN MAX PER MODIFIER Humans = 3 - 18 = 0 Elves 4 - 19 +1 Half-Elves = 3 - 19 = +1 (50% chance) Dwarves 2 - 17 -1 (+1 to taste) Gnomes = 3 - 19 = +1 (to sight -- Tinkers only) Halflings 3 - 18 0 (+1 to taste) Elves have excellent sight; they have a +1 to their PER, while Dwarves have a -1. Tinker Gnomes have a +1 to vision while other Gnomes do not. Humans and Halflings are unchanged. Of the humanoids, PC Minotaurs gain a +5 with respect to their Perception of smell (not sight or sound). Satyrs also receive a bonus for keen senses, +2. Orcs and Goblins have a penalty of -2 to PER when in daylight or when subject to a *continual light* spell. Thri-Kreen, because of their antennae, receive a +2 to PER checks concerning motion detection. In relation to aging affects, subtract -1 when a character reaches Old Age and -1 when Venerable is reached. This affects both sight and hearing, but the other senses do not normally degrade over time. USING PERCEPTION. To put it as simply as possible, Perception should be applied whenever there is a possibility of detecting something with one of the five senses. Lacking a specific Perception-like statistic, most DMs use INT or WIS checks to see whether a character or NPC notices something peculiar in front of him, or whether he might have heard an unusual sound, or something to that effect. Perception replaces such rolls, although under some extraordinary circumstances the PER check may need to be modified according to the individual's INT or WIS, such as disbelieving illusions. Some may notice that psionics are not dealt with in this NetBook. I felt that going anywhere near psionics with this would be subjecting myself to the debate about whether psionics should be considered a "sixth" sense, about whether there should be modifiers to telepathic powers, whether contact should be modified, attack modes, et cetera ad nauseum. I am arbitrarily leaving this up to those DMs who use psionics. For the most part this NetBook only concerns itself with those rule systems within the AD&D game that are accepted as universal. VISION VS. HEARING VS. OTHER SENSES. To determine Vision and Hearing aspects of Perception, take triple the PER score and distribute them among sight, hearing, and other. A 10 PER can be a 5 Vision, 15 Hearing, and 10 Other, suggesting a character who needs good glasses, has ordinary taste/touch/smell acuity, but can pick up a whisper from across the room. >> PERCEPTION AS VISION The following chart shows the meanings of PER in terms of vision. In references to specific objects (like cells), the distance from eye to object would generally be six inches to one foot or from eye to table while one is seated. PER/VISION DESCRIPTION OF EFFECTS SCORE 25 = Can perceive subatomic particles 24 Can distinguish substances from one another by their atomic configuration 23 = Can perceive virii or parts of cells 22 1,000/1 (1000x normal), or cells in detail 21 = 500/1 (500x normal), or small cells as normal 20 100/1 (100x normal), or small protists as normal 19 = 50/1 (50x normal), or fine hairs as normal 18 20/1 (20x normal), or thread fibers as normal 17 = 20/2 (10x normal), or microwriting as normal 16 20/5 (4x normal) 14 to 15 = 20/10 (2x normal) 12 to 13 20/15 (1 1/3x normal) 9 to 12 = 20/20 8 to 9 20/40 6 to 7 = 20/60 5 20/120 4 = 20/200 3 20/400 (legally blind) 2 = Legally blind, but can detect varying light levels 1 Legally blind, but can only detect very bright light (such as sunlight at noon or continual light) 0 = Legally blind, cannot detect any light level; both eyes are destroyed, missing, or nonfunctional from birth or other mishap. MISSILE AIM. The PER modifier to aiming a missile weapon at distance is identical to DEX of the same magnitude (a DEX of 16 and a PER of 16 gives the same bonus of +1 to attack) -- both PER and DEX modifiers are cumulative for attacking. As before, a creature is assumed to have a PER of 10 or 11 if no score is expressly indicated. VISIBILITY RANGES. Visibility Ranges for perception, as shown on page 117, follows. For each +1 to Visibility, one may detect one category to the left with respect to environment; i.e., +1 means one can detect at "Spotted" distance, something at "Movement" distance; or detect "Detail" at "ID" distance. For every +1, maximum detection range is increased by a multiple of the Movement distance movement according to the Condition (i.e., a +1 while in Clear Sky will offer a maximum Movement detection of up to 3,000 feet. These are not meant to be scientifically accurate, but are as a general indicator of the benefits of good vision. VISIBILITY RANGE CATEGORY MODIFIERS PER/VISION CATEGORY SHIFT SCORE LEFT OR RIGHT 22+ = +4, or 4 columns to the left 18 to 21 +3, or 3 columns to the left 16 to 17 = +2, or 2 columns to the left 13 to 15 +1, or 1 column to the left 9 to 12 = unchanged 6 to 8 -1, or 1 column to the right 3 to 5 = -2, or 2 columns to the right 1 to 2 -3, or 3 columns to the right 0 = no visibility MELEE THAC0 MODIFIERS. Melee attacks may be affected by a character's vision. Depending on the sort of attack being made, good or bad vision may or may not have a bearing on its success. In addition, AC can also be affected, through being able to detect where an attack might come from or whether an opponent is going to try a thrust to the torso versus a slash from the side, and so forth. Where AC is handicapped by poor Perception, this only applies when a character has suddenly found himself with poor or lack of sight or hearing. He may have been blinded through accident or punishment, or he may have had an inner ear infection which deafened him. Individuals who have adapted to the loss or absence of one sense through the honing of another do not suffer this penalty (people who have known a deaf or blind person can attest to this). As a suggestion, a person suffering from the AC handicap may reduce his penalty by -1 for each level beyond the level when he first received his impairment. While little can be gained in melee combat with an 18 vision, ranged shots can be improved by a little. PER/VISION NORMAL CALLED RANGED SCORE SHOTS SHOTS SHOTS AC 25 = +1 = +3* = +5** = +2 24 +1 +3* +4** +2 23 = +1 = +3* = +4** = +2 22 +1 +2* +4** +2 21 = +1 = +2* = +4** = +2 20 +1 +2* +3** +2 19 = +1 = +2* = +3** = +2 18 +1 +2* +3** +2 17 = +1 = +1* = +2 = +1 16 +1 +1 +2 +1 15 = 0 = +1 = +2 = +1 14 0 +1 +1 0 13 = 0 = 0 = +1 = 0 9 to 12 0 0 0 0 9 = 0 = 0 = -1 = 0 8 0 -1 -1 0 7 = 0 = -1 = -2 = -1 6 -1 -3 -3 -1 5 = -1 = -3 = -5 = -2 4 -2 -5 -7 -2 3 = -4 = -9 = -10 = -3 2 -8 -17 -18 -4 1 = -12 = -25 = *** = -6 0 -18 *** *** -9 * The attacker can make a more precise called shot, such as between two parts of a sectioned suit of armor (at the shoulder joint, elbow, eyehole, etc), provided a Quality piercing weapon is used -- weapons of ordinary construction will not have adequate aim. ** Called shots can be made at one range category better than normal, assuming a weapon of Quality is used -- weapons of ordinary construction will not have adequate aim. *** An impossible shot (successful attack only with a 20) >> PERCEPTION AS HEARING The following chart shows the minimum sound detectable at an average distance from across an average-sized room: 25 = any motion of atoms on the atomic level 24 any current of air regardless of temperature 23 = normal motion of air as excited by sunlight from an open window 22 any motion of air produced by mov. of insect-size creatures * 21 = any motion of air produced by Tiny creature movement * 20 any motion of air produced by Small creature movement * 19 = any motion of air produced by any creature or object movement * 17 - 18 1 dB, or soft human heartbeats (below normal hearing) 15 - 16 = 5 dB, or loud human heartbeats (just above possible hearing) 9 - 12 10 dB, or very quiet whispering 8 = 20 dB, or moderate whispering 7 40 dB, or soft music 6 = 60 dB, or normal conversation 5 90 dB, or loud music 4 = 120 dB, or the normal threshold of pain 3 150 dB, or the volume of a jet airplane engine 2 = 200 dB, or the sound of a great tornado a few feet away 1 the sonic breath of a great wyrm emerald dragon 0 = completely deaf, the inner ears are destroyed, missing, or nonfunctional from birth or other mishap. * Movement is designated as little more than waving one's hand / arm / wing / tentacle / etc, levitating across the floor, etc. I HEAR THE SOUND OF DECIBELS IN THE DISTANCE. I am by no means an expert on volumes of sound. Should anyone be able to provide me with a suitable comparison of actual decibels to characteristic sound levels, please do so; it will much improve the hearing section of this NetBook. THIEVING SKILLS. Thieves depend on their senses for their talents. Perception percentile modifiers to thief skills are shown below as percentage modifiers. PERCEPTION MODIFIERS TO THIEF SKILLS PER OR DETECT F/R HEAR NOISE TRAPS SCORE MODIFY MODIFY 25 = AUTO = AUTO 24 AUTO AUTO 23 = AUTO = AUTO 22 AUTO AUTO 21 = AUTO = +99% 20 +99% +80% 19 = +80% = +60% 18 +60% +40% 17 = +40% = +20% 16 +30% +10% 15 = +20% = +5% 14 +15% nil 13 = +10% = nil 11 to 12 +5% nil 9 to 10 = nil = nil 8 -5% nil 7 = -10% = -5% 6 -15% -10% 5 = -25% = -10% 4 -35% -20% 3 = -50% = -30% 2 -70% -40% 1 = -95% = -50% 0 NDP NDP AUTO Automatic success (fail only on a 01%) NDP No detection possible (skill is useless) PERCEPTION VS. DEXTERITY. The following chart indicates the bonus or penalty incurred against someone's PER check to hear non-thief movement, via high or low DEX. A guard will incur a penalty of -2 to hear the sound of a non-thief (or thief not using Move Silently) having a DEX of 13 and trying to creep past or otherwise get by without detection. MODIFIERS TO OPPONENT PERCEPTION CHECK VS. DEX DEX PER SCORE MODIFY 25 = AUTO 24 -50 23 = -37 22 -25 21 = -18 20 -12 19 = -7 18 -4 16 to 17 = -2 13 to 15 -1 9 to 12 = nil 8 +1 7 = +2 6 +3 5 = +5 4 +6 3 = +10 2 +14 1 = +19 0 N/A LANGUAGE COMPREHENSION. Severe loss of hearing may hamper the ability of the character or creature to understand what someone is speaking to him. There is a percentage chance to misinterpret the words of verbal speech or to otherwise fail to grasp the complete message. This percentage may aggravated by background noise or other factors, determined by the DM. One's PER/Hear score where understanding one's native language is concerned is treated as a +3 due to familiarity with the language. Thus a person with a PER of 5 (a 25% misinterpretation) can comprehend his native language as if he had a PER of 8 (a 5% misinterpretation). Whether or not this can apply to more than one language for any one character is dependent upon the DM's decision about such things as being bilingual from childhood. Successful application of the Reading Lips proficiency will negate the possibility of misinterpretation, although imperfect comprehension is still possible (see description of this proficiency on p. 61 of the PHB). MODIFIERS TO LANGUAGE COMPREHENSION PER/HEAR PERCENTAGE SCORE OF MISINTERPRETATION 8 = 5 % 7 = 10 % 6 = 15 % 5 = 25 % 4 = 35 % 3 = 50 % 2 = 70 % 1 = 95 % 0 = NCP NCP No comprehension possible (cannot hear speech) >> OTHER EFFECTS OF PERCEPTION PERCEPTION/OTHER SENSES: If a player chooses to "specialize" in Other instead of Vision or Hearing, he must indicated which of the other three senses are above the norm. He must have either a sensitive nose, sensitive taste buds, or sensitive touch. There are advantages for every sense, and an industrious character can usually find work exploiting this talent like he could any other. Examples include tasting for poison or simply being a wine conniseur (sp?), being able to track a scent, or being widely known among the members of the opposite sex for one's massage technique (grin). How such talents would fit into the Netbook of Unlawful Carnal Knowledge, one can only imagine (but I will leave that to those who want to do so). LOSS OF EYES OR EARS. If only one ear or eye is missing or deafened, the character incurs a -2 penalty to PER checks where the affected sense is concerned. In addition, there is a -4 penalty against PER checks to determine the direction of a particular heard sound or to approximate the distance of something seen. This penalty diminishes by -1 per round of concentration, however, such as turning one's head to notice changes in volume of a sound, or by comparing the sighted object to the estimated distance of other objects of known height (trees, buildings, humans, etc.) EFFECTS ON PROFICIENCY CHECKS. The introduction of this PER system will of course affect the use of some proficiencies and skills, particularly those which require a good eye or ear in order to succeed. A list follows of what proficiencies might be slightly, moderately, or severely affected, if vision or hearing were reduced significantly. For each proficiency, it should be obvious which of these senses would apply, although the character can rely on the other three senses (smell, taste, and touch, but almost universally touch). Many individuals could also rely on sheer intuition, rote training, or deft magic or psionic use for some degree of success. If the character's sight or hearing is adversely affected, any proficiencies relying on the affected sense are penalized by a certain percentage, shown below. In contrast, Blind-Fighting is partially dependent on sound and intuition and training. While poor or disabled vision will hamper a character's THAC0 rolls, use of Blind-Fighting will negate this penalty. Proficiencies indicated include those from the Skills & Powers book as well as from the Player's Handbook. Penalties to some proficiency checks can be halved if the character attempting the check has the help of another who can act as his "eyes" or "ears", as applicable. PROFICIENCY PENALTY SENSE USED Appraising -4 * sight Artistic Ability ** sight Blacksmithing ** sight Boat Piloting -4 sight Carpentry -2 sight Cobbling -2 sight Cooking -2 sight & taste Cryptography -4 * sight Deep Diving -8 sight Engineering -4 sight Fire Building -4 sight Fishing -4 sight & touch Gem Cutting -2 sight Mining ** sight Navigation -8 sight Reading/Writing -8 sight Painting -8 sight Singing -4 hearing Survival -4 * sight & hearing Tailoring -2 * sight & touch Tightrope Walking -2 * sight Tracking ** sight & smell Weaving -2 * sight & touch Weaponsmithing ** sight * Proficiency penalty cannot be alleviated by help from others. ** Proficiency is unusable if sense used is disabled. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (c) 1997 by Xeno, where applicable. E-MAIL ADDRESS: mlsheltn@cc.memphis.edu WEB PAGE: http://www.people.memphis.edu/~mlsheltn Creator of the NetBook of Heretic and the Puritan class. Created: 7 February 1997 Revised: 12 February 1997 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ the little man who thinks big thoughts, O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O=O= *XENO* (a.k.a. Matthew Shelton) Creator of the NETBOOK OF HERETIC EMAIL ADDRESS: mlsheltn@cc.memphis.edu and the PURITAN WEBPAGE URL: http://www.people.memphis.edu/~mlsheltn character class Guns are not a problem. It is the criminals who own the guns that are the problem. The only thing wrong with gun-control laws is that only law- abiding people are going to give them up. -RUSH LIMBAUGH III (paraphrased) o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-o-