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Jo'Mase's AD&D Misc. Rules


The Perception Ability Rating

Perception is a trait all creatures possess to some degree. It is used for any check related to observation, alertness or scrutiny. To determine the base rating for a creature, just add his INT and WIS scores together, and divide by 6(round off). Perception is just like a NWP skill, in that it falls into the 4 skill rankings of : Novice, Skilled, Expert and Master. Just reference my Proficiency Rules page for details on this. Creatures get to improve their perception naturally, and get 1 proficiency point each level or HD they possess to boost their rating. Apply the same rules for this boosting as are applied for NWP(see Proficiency Rules). These PPs are the only ones a creature can spend to improve his perception, none of his 3 PPs he gets each level for general NWP skill improvement can be used for perception. Only if the creature takes the Observation/Alertness skill(both are now the same skill, and have no ability base themselves, but simply modify the perception score), can this restriction be ignored. By spending 1 proficiency slot on this skill(now a General Category skill), the creature gets 3 PPs to immediately spend on boosting his perception rating, but is still restricted to at most a 1 point rating increase per level, before the penalties for increasing it more apply. He can save his PPs, in this case, if he desires, to spend them at later levels as he is able. Also, by acquiring this observation/alertness skill, he now is able to use the 3 PPs he gets per level for NWP skill improvement to improve his perception rating if he so chooses.

Racial Modifiers

Elves and drow get 3 PPs extra to improve their perception scores at creation. Half-elves get 1 PP extra.

Perception and its Applications

Perception is used now to determine the chances to find secret/concealed doors, to determine surprise and to detect hidden/invisible creatures. Other similar perception based checks will also use perception to determine success or failure.

Secret/Concealed Doors: to find secret doors, a normal PER check is required, while concealed doors require a PER check with a +4 bonus. If a PER check with a -4 penalty is made(thus, because it requires a -4 penalty to try this, only Skilled or better rankings can attempt it), a concealed door is seen if the person passes within 10’ of it. Every 5’ extra beyond this 10’ minimum requires an extra -1 to the check to notice the concealed door merely by passing by it, so only Expert or Master rankings can attempt this feat.

Surprise Checks: standard surprise checks, with no modifiers for noise of approaching party, or other such clues which might make surprise less likely, are normal PER checks. Each side rolls its PER check, and if 1 side succeeds while the other fails, the side that failed is surprised. If both fail their PER checks, or both succeed, then no surprise results for either side. The bonus surprise gives comes in 2 forms: an attack of opportunity, and a base of 3 action phases before the surprised side can react. The attack of opportunity can only be gained if the individual is within melee range and has a weapon ready, or has a missile weapon loaded/notched and ready. No magic item or spell power can be used in this free action, only a single shot/attack from a melee/missile weapon. After this, the individual can take actions as he would normally in a melee round, but need not roll initiative. Just determine how many such actions the individual could take within 3 action phases, because at the end of the Average phase(the 3rd phase of this special free half-round), normal combat begins, with initiative and actions as usual. During any attack when a target is surprised, he cannot oppose any attack, neither use a shield or any of his Defense Pool/Combat Defense. Those with DEX reaction bonuses can reduce the number of free phases a foe receives against them, by 1 phase per +1 of reaction modifier. This can eliminate up to all 3 free phases, if the DEX bonus is high enough, but the attack of opportunity the foe receives is still always granted, regardless of DEX bonus. Those with a DEX penalty, likewise, actually suffer more of these free phases, as the foe receives an extra free phase for each -1 reaction penalty.

Detecting Invisible Creatures: if a creature makes his PER check with a base -4 penalty(so only Skilled rankings can even attempt this), he senses the invisible presence, and can detect it enough to attack in its general area, suffering the usual penalties for attacking invisible targets. Of course, if the invisible person is also silent, he will apply more penalties to this PER check, as the DM may impose. If the invisible person makes no attempt to conceal his presence(ie. is loud, gives away his position in some way, etc.), then only a normal PER check is needed to detect his general location, with potential bonuses depending on his actions, as the DM may impose.

Hitpoint/Damage Rules


Each time a creature suffers a big chunk of damage from a single attack, there is a chance for a special wound result. Wounds that cause damage equal to or greater than the damage threshold of the creature(see below) in a single hit are serious wounds. Wounds that cause damage equal to or greater than twice the damage threshold of a creature in a single hit are critical(mortal) wounds.

-Serious Wounds: can only be fully healed by a cure serious wounds spell or other healing power able to restore 20 hitpoints in a single use, or enough natural healing to restore 25 hitpoints. Until healed, this wound causes the creature a -1 to hit and damage from the pain it causes and increases his encumbrance level by 1 step. Additionally, the wound will bleed 1 hitpoint/turn for every 4 points of damage the attack did(spread this hitpoint loss across each turn as evenly as possible). Bandaging will reduce the bleeding damage taken to half normal, but does not change the actual bleeding rate. Every turn, the wounded individual must make a save vs. death(with a +4 bonus if tended to by a person with Healing skill), and if it is successful, the bleeding rate is cut in half for the next turn(a rate of 1 point/turn is reduced to 0 in this way), and if reduced to 0, the bleeding stops. Healing can reduce this bleeding rate as well. For every point of healing given to such an individual, if it does not totally heal the wound, it will at least reduce the bleeding rate by an equal number of points per turn as it healed. So one who suffers 5 points of bleeding per turn who is healed by a 4 point cure spell, would only bleed 1 point per turn.

-Critical Wounds: can only be fully healed by a cure critical wounds spell or other healing power able to restore 40 hitpoints in a single use, or enough natural healing to restore 45 hitpoints. Until healed, this wound causes the creature a -2 to hit and damage, and a +1 AC from the pain it causes and increases the encumbrance level of the wounded individual by 2 steps. Additionally, the wound will bleed 1 hitpoint/turn for every 2 points of damage the attack did(spread this damage across each turn as evenly as possible). Bandaging will reduce the bleeding damage taken to half normal, but does not change the actual bleeding rate. Every turn, the wounded individual must make a save vs. death(with a +4 bonus if tended to by a person with Healing skill), and if it is successful, the bleeding rate is cut in half for the next turn(a rate of 1 point/turn is reduced to 0 in this way), and if reduced to 0, the bleeding stops. Healing can reduce this bleeding rate as well. For every point of healing given to such an individual, if it does not totally heal the wound, it will at least reduce the bleeding rate by an equal number of points per turn as it healed. So one who suffers 5 points of bleeding per turn who is healed by a 4 point cure spell, would only bleed 1 point per turn.


Recovery Rate(natural healing)

All creatures recover hitpoints naturally at a monthly rate equal to their damage threshold(see below). This assumes the wounded creature has had his wounds tended/bandaged by a healer(one with the healing skill at rank skilled, or with both healing and herbalism at any rank) remaining under his care, and engages in very minimal activity, with lots of bed rest(this replaces the info in the PHB, and healers cannot heal wounds instantly of d3 points as in the PHB). If no healer was available, then the standard first aid any adventurer can administer will allow the wounded to recover at half(rounded down) this rate, as long as someone is there to care for him through this period. Wounded who do not rest, further halve their recovery rate(rounded down).

Wounds should be checked for infection, with serious wounds doubling and critical wounds tripling the chance. Healers will cut this chance in half, for each rank of skill they posses above novice, with herbalism further adding to their effective rank for this purpose half(rounded down) of the skill ranking of the herbalism skill. So skilled healers cut the chance in half, experts by 4, masters by 8. If also skilled or expert in herbalism, further halve the chance, if a master, further quarter the chance. The base chance for infection is 10%, which is checked each month the wound remains. The effects of this infection are up to the DM, but can easily be fatal if uncured.

Magical Healing Limitations

Healing spells and powers are limited to a total healing effect of the maximum healing possible from the power, for any single wound. Once this limit is reached, further healing by this power, or lesser powers(those with a lesser maximum healing potential) is not possible, and such attempts are wasted. This applies regardless of where the power comes from, so even if 2 priests can cast a cure light wounds spell(maximum of 8 points healing), they could not cure a specific wound more than 8 points total(even though the 2 spells could roll 16 points of healing, once a creature has been magically healed for 8 or more points, cure light wound spells become useless, regardless of who casts them). This makes more powerful healing spells very important to creatures who have taken severe wounds, as the minor healing powers will soon max. out, leaving the creature still wounded.

This healing limit applies to specific wounds, not to the creature as a whole. Each hit inflicts a separate wound, so a hit that does lots of damage will inflict a severe wound only powerful healing can help fully.

First Aid to Dying Creatures

Anyone with healing proficiency or any priest with major access to healing sphere(no spell casting needed for this benefit), can stop the 1 hitpoint per round loss of creatures at 0 or less hitpoints. Those with Herbalism or survival(or any such skill the DM feels would assume at least basic first aid knowledge) can try to stop such hitpoint loss, but must make an INT check to succeed. They can continue to try, making more INT checks, if their earlier attempts failed or were negated, each such attempt requires a full round. Those with no first aid training are assumed to know the very basics at least, and so can try to stop such hitpoint loss by passing an INT check, but using only their INT. Individuals trying to bandage their own wounds can do so, but any checks they are required to make are at -4 due to the trauma they are suffering.

-Recovery From Near Death: any creature who was reduced to 0 or less hitpoints can be stabilized(brought to 1 hitpoint) by magical or psionic healing. Natural healing may allow such a creature to recover on it’s own, but the creature would require a healer’s care at least to have any hope of such natural recovery. If the creature is forced to recover via natural healing, he must pass a save vs. death(add/subtract is CON bonus or penalty to hitpoints to this save), success indicates the creature recovers to 1 hitpoint in 1 week, failure means the creature will not recover naturally, and only magic can save him. If a creature does not recover in 1 week, each week thereafter, the creature must pass a save vs. death, or pass away. Creatures healed to 1 hitpoint must rest a full day before they can gain further healing. During this time, they are conscious, but considered stunned. Only a Heal spell or greater will allow such a creature to fully recover and assume normal activity. Also, if the creature is stabilized, the full day rest requirement can be removed with a Cure Critical Wounds spell.

Damage Thresholds

All creatures/PCs have a damage threshold, which details the limit of physical pain/trauma they can suffer without serious and immediate penalties. To calculate this threshold, divide the PC’s CON by 3, rounding off, and then add their level modifier. Warriors and priests add their level to their CON/3, while rogues and wizards add half(rounded down) their level to their CON/3. Monsters or creatures who have no CON statistic simply use the average(rounded up, monsters are tough) of their hitdie, which is a d8, so they use 4.5 which rounds up to 5 as their base, and add their HD to this. Bonus points to the HD count as another HD for every +4 points. This will give the damage threshold for the creature/PC. 0-level creatures simply use a common threshold of 4, unless their CON is known, in which case they use their CON/3, but get no level bonus to this. 0-level soldiers, count as 1 HD, so they add 1 to their threshold(assume 5 if CON not known).

Any time a creature suffers damage equal to or greater than this threshold value, with stun damage counting just as much as real damage for this purpose, he must save vs. death or be stunned. This save has a penalty equal to the number of damage points the attack did over his threshold. If the save fails, the target is stunned. He remains stunned for 1 round, and then can make another attempt to save, with the same penalty, but with a +1 bonus. If he succeeds, he is no longer stunned, but failure indicates he is stunned another round, when he can save again, with a +2 bonus. This bonus increases by +1 every round the target remains stunned, until he finally recovers by making his save. Hard blows can really stun a target for a long time, potentially! If the target critically fails his saving throw, that is, rolls a 1-3 and misses the save by 5 or more, he is knocked out cold instead, and can roll a new saving throw at the same penalty, but with a +1 bonus after a full turn, success indicating he awakens. If he fails, he remains unconscious for another turn, at which point he can make another save with a +2 bonus, repeating this procedure as often as needed.

The above is the usual application of damage thresholds, but called shots also take them into account, to determine special wound affects. See below, under Called Shots for details.


For warriors of extreme skill and prowess in their technique, there comes a time when the standard "I hit the nasty beast with my trusty Hackmaster +12" just does not cut it anymore. Their skill is such that landing a blow is no longer as challenging, neither as difficult as it was during their former levels. They meet monsters whose armor or powerful/deadly attacks require that they use their enhanced skills to the fullest, rather than just wasting those skills on a simple and often less effective normal attack. For these, the few, the proud, the PCs we have such an option open to them.

The Called Shot

Every called shot requires some timing and delay, as it requires this to set up the special shot and make it work. Thus, each of the special shots I will detail below will have a to hit penalty only associated with it, and perhaps a special side requirement as well. The delay and basic difficulty modifier inherent in any called shot in the middle of chaotic melee is subsumed in the Standard Called Shot Penalty. This standard penalty applies to all called shots, and each special shot’s to hit penalty is added to this base penalty to find the total penalty for the shot.

Standard Called Shot Penalty

This standard penalty which applies to all called shots is simply:

a -4 to hit penalty.
a +3 initiative delay.

This penalty applies to all such shots, and can only be removed in cases when a warrior specifically trains in the skill to remove 1 or more of these penalties.

Location Based Called Shots

A shot aimed at a body part falls under this classification.

Arms/Legs/Wings/Tails or Other Extremities

This shot requires no additional penalty to take as long as the area attacked is not behind a shield or other cover, in which case it would fall under the classification below. Any such shot to these areas has a chance to score a special effect. See Called Shots Special Effects below.

Head/Vital or Opposed Shots

If a creature can oppose any shot to his head or vitals, or the area attacked is behind a shield or cover(like the shield arm and vitals, even the legs when body shields are used), the attack requires an additional -4 to hit. If the head or vitals is attacked and the creature cannot oppose it(such as when attacked from behind or the flank, or when a creature is overwhelmed by more attacks than he can handle), it requires no extra penalty to attack.

The effect of hitting the head or vitals is that the attack gets a +2 AR and +2 to knockdown rolls. In addition, as with limb shots, special effects may occur, see Called Shots Special Effects below.

Critical/Damage Shots

Those shots that seek to strike a critical or inflict extra damage fall here.

Critical Strike

This shot will inflict a critical hit if it lands, as long as it still hit by 5 or more. If you roll in your usual critical range, and still hit by 5 or more, you can apply half of this -4 toward either the save penalty or severity increase detailed next. It requires an additional -4 to hit, and for every extra -1 to hit the attacker takes above this, the foe saves against the critical at -1 per extra -1 taken. Or, the attacker can opt to increase his severity roll by +1 per extra -1 he takes to hit. This severity roll bonus can only increase the severity roll up to the normal maximum allowed by the roll, any extra is just lost. These additional special effects can be used together.

Skill Shot

This shot seeks to do maximum weapon damage, which it does if the shot hits. This requires an additional -4 to hit. If the attacker also wishes his knockdown die to score a maximum roll, this can be added for another -4 to hit. Additionally, when seeking knockdowns, every extra -1 to the shot gives the knockdown roll a +1 modifier.

Wound Targeting

This shot seeks to strike at a previously inflicted wound, to make it worse, deepening it. To make this shot, requires the usual called shot to the area the previous wound was inflicted on, but with an additional -4 to hit. If the previous wound was not a called shot wound, it cannot be targeted in this way, only previously targeted wounds, via a called shot, are sufficiently localized to be targeted in this way. If the blow strikes, it causes damage normally, as the called shot would allow, but the damage inflicted is not treated as a separate wound, but added to the damage of the previous wound, and the total becomes the new severity of the wound. This allows multiple attacks to act as if a "single" attack, which can generate special effects if enough damage is done.

Armor Shots

These are shots that seek to bypass an opponent’s armor, or exploit a weak point in his armored defense.

Bypass Armor

This shot is effective only against those who wear armor(as opposed to natural body armor) and who do not wear a full suit. The area left unarmored can be struck, and the shot will ignore that foe’s armor value, though toughness always counts. This is usually just an area called shot, so use those guidelines above. However, in the case of a helmeted foe, who has an open faced helmet, a shot can be aimed at his face, which ignores the armor, but requires an additional -8 to hit. This shot will get both the benefit of ignoring armor, and the special effect of a head shot, detailed above. Also, such a shot forces the target to save vs. Death or be blinded in 1 eye.

If the helmet is a visor helmet, and the visor is up, only a thrusting/piercing weapon can exploit the face to full effect as above, with an additional -8 to hit. Other weapons can still hit the face area, but the foe still receives half his armor against it, though is still vulnerable to being blinded, as above.

If the visor is down, only weapons designed for slipping into it can still try this attack. Stilettos, rapiers and other weapons with narrow tips, can still attack, with the above penalty, but the visor will still offer the foe some shielding, so half his armor still counts. This attack also has a chance to blind the target, as detailed above. A good grab attack to pull off the helmet(assuming it is not secured) or at least lift the visor comes in handy here, if the attacker is good enough.

Exploit Armor Weakness(Standard)

This shot works against those who wear composite armor, like plate mail, and those with natural armor that is hide based in nature. These armors have weak points that attackers can exploit, with an additional -4 to hit penalty. The shot cuts the armor in question in half(round down) with regard to its defense. Those in full armor or plate or monsters in chitinous or scaly armors cannot be exploited in this fashion, but are dealt with below.

Exploit Armor Weakness(Special)

For those in full suits or monster armor, the armor is so protective, and covers the most vital areas, that getting around it is really next to impossible. The visor shots detailed above work for plate armors, but against monsters, a similar shot might be allowed. The face or eyes are the areas that might prove effective when attacking such an armored beast, but not always. Generally, such a shot requires the attacker to hold and wait for the monster to strike and expose the vulnerable area, so the attacker who seeks to use this must allow the beast to strike first, and assuming he survives this, he can attempt this shot. The attack requires an additional -8 to hit, as with a face shot, since you are striking only small areas of the face, the rest being armored. If the shot hits, the armor of the beast is halved, and it must save vs. Death or be blinded in 1 eye. As you can see, this shot is very difficult.

In some cases, a monster may have a vulnerable area, like Smaug in the Hobbit, but this is only in some cases, like when a surviving dragon of a dragon fight has portions of his armor in the neck area ripped away, or such. If such a flaw exists, then a PC can attempt(using 1 action per attempt) to spot it. This requires a Perception roll, and those with an Expert perception or more get a free check each round. The smaller and less accessible the spot, the more the penalty to the perception check. You may be checking against a foe that has no weakness at all, you can never be sure, so this is a last resort option in the heat of melee, and it is wise to gain such knowledge ahead of time. If the spot exists, a shot at an additional -8 to hit will allow all armor to be ignored.

Combining Called Shots

All of the above shots can be used in concert with each other, just add up the penalties, adding in the Standard Called Shot Penalty only 1 time. Thus, it is common for warriors to have favorite or signature moves they can design on their own using these shots as a base. These moves/shots can be combined with existing maneuvers, and the DM can allow a reduced shot penalty if the shot must be combined with another move to work. For example, if a PC must successfully dodge/parry an attack first, before he could use a special called shot, the penalty for that special shot could be less than normal, as the pre-requisite of dodging/parrying allows the penalty to be reduced. Some may require pre-requisite skills to use, like martial arts styles, or Blindfighting, or weapon mastery, and in these cases, the penalty can also be reduced to some degree, but the DM must carefully balance these shots to fit into his own campaign.

Called Shots Special Effects

Called shots(not random hits(like for beholders) or random critical hit locations) can disable foes limbs. If the damage done by the attack(must be caused by a single attack) is equal to or greater than the damage threshold of the target, the target must save vs. death(with a penalty of -1 for every point of damage done above his threshold) or the area is useless until the damage is healed, or a d6 hours pass. Even then, if not healed, all actions taken by that limb are at -4. Additionally, every additional hit to that area, until healed, forces the save vs. death(no penalty) or the area becomes useless as above. Head or vitals shots of this type will knock out the target if he fails the save, but he remains unconscious until the wounds are healed, or a d6 hours pass. Even then if the wound is not healed, the person will be dazed, and all actions will be at -4. Until healed each additional hit to the same area forces the save vs. death(no penalty) or the wounded individual falls unconscious as above. These effects are in addition to the usual effect of equaling or exceeding a foe’s damage threshold, detailed above, under Damage Thresholds.

If an area suffers cumulative damage, from a set of called shots, equal to or greater than twice the creature’s threshold, the same effect applies as above, as if a single blow equaled or exceeded the threshold. However, if a blow actually inflicts damage equal to or greater than twice the target’s threshold in a single blow, the area targeted is affected as if a critical hit were rolled against it, and a 12 severity was rolled! The target gets no save against this!

Collateral Damage:

Fire, cold, acid, gas and lightning attacks can have side effects(most are covered in PO: S&M, these are extra effects in my campaign):

FIRE: as detailed in PO: S&M, nothing extra added.

LIGHTNING: if the target(s) fail their save and take full damage, then they must make another save, a save vs. death or be stunned. They remain stunned until they finally make the death save. They get a new chance each round with a cumulative +1 bonus each round they fail.

ACID/GAS: these attacks will do damage over a longer period, but the base damage of such attacks assumes this, just dealing it out all in the 1st round. The other effect these attacks can have is system shock. As with lightning above, if the target(s) fail to save and take full damage, they must make a save vs death or be stunned from the shock to their system. The stun lasts until the target finally saves as in lightning above.

COLD: this type of attack will cause the target(s) who take full damage(fail to save), to have numbed extremities and slower reactions. The target is slowed(as the spell) if it fails to save vs death. It recovers when it finally makes the save, as in lightning above.

Calculating Carrying Capacity/Encumbrance:

Instead of using the AD&D system, just base encumbrance on the Max. Press of the STR score of the individual. He can carry up to 1/5th his Max. Press score and be unencumbered. Up to 2/5th's will make him lightly encumbered, up to 3/5th's will make him moderately encumbered, while up to 4/5th's make him heavily encumbered. Any load above 4/5th's the Max. Press makes the individual severely encumbered.

-Mounted Encumbrance: while mounted, a rider only counts half his armor weight to figure encumbrance.

Encumbrance Penalties

Light Encumbrance: 

 reduces AC/Initiative and DEX checks by 1 point.

Moderate Encumbrance: 

 reduces AC/Initiative and DEX checks by 2 points in addition to reducing both attack and
damage rolls 1 point.

Heavy Encumbrance: 

 reduces AC/Initiative and DEX checks by 3 points and attack/dmg rolls by 2 points.

Severe Encumbrance: 

reduces AC/Initiative and DEX checks by 4 points and attack/dmg rolls by 4 points.  

Encumbrance/Armor and Knockdowns:

Normally a knocked down person can rise by spending an attack or a half-move, but encumbered/armored people have a harder time of it. Below are the details required of those encumbered to rise from a prone position. During the time any creature is attempting to get up, all attacks are at +4 to hit, and the person rising up cannot apply DEX or any similar dodge bonuses to his AC. Only a shield offers any protection. Heavy armors(chain mail or heavier) always require a full round(or 2 actions) to rise from a prone position, even if the wearer is unencumbered. However, proficiency in the armor will remove this penalty.

-Light Encumbrance: these folks lose initiative on the round they rise.

-Moderate Encumbrance: these individuals require a full round to rise up(or 2 actions, whichever is less).

-Heavy Encumbrance: these individuals require a full round(or 2 actions) to stand, and if in melee, must pass a DEX check(fully modified for armor and encumbrance) each time a hit is scored or fall back down again. Even if no hits were scored, just being in melee requires at least 1 DEX check to stand.

-Severe Encumbrance: these folks are in a bad way if knocked prone. They cannot rise unaided if in melee. Only if unhindered by attackers can such a person attempt to stand. They must pass a DEX check to stand.


Damage bonuses for STR on missile weapons(all missiles, hurled, shot, slung, etc) are limited to the max. base damage the weapon can do, magic or exception weapons do not increase this, but the grandmaster's base weapon damage die increase does. Thus a sheaf arrow which does d8, allows a maximum of +8 STR damage applies. Darts(d3) can have +3 max. Missiles get no to hit bonus from STR, only from DEX.

Also, missiles fired over short range have their critical base number reduced by 1 for each range beyond short. Thus a fighter has an 18-20 at short, a 19-20 at med., a 20 at long and no chance if he can shoot at extreme range. A grand master has a 15-20 at point blank, a 16-20 at short, a 17-20 at med., an 18-20 at long, and a 19-20 at extreme ranges.

In a similar way, bows, crossbows, slings, and firearms have their damage reduced over range. The wind resistance tends to slow such high velocity missiles down over long distances. Each range category beyond short range, reduces their damage1 point. For example, a sheaf arrow which does a d8 at short range, does d8-1 at medium, d8-2 at long, and d8-3 at extreme ranges.


The stoneskin spell does stop all physical damage, but does not stop stun damage inflicted by blunt type attacks or AR bonuses. To determine the stun damage that gets through a stoneskin defense, treat the stoneskin as giving the defended individual a temporary AV equal to the damage the attack would normally inflict, after reducing it for any armor or toughness the individual might have. First determine the number of real damage points that would have gotten through normally to the individual, any left over stun damage from the initial impact is ignored. Give the skin of the individual an AV equal to this real damage that gets through. Blunt attacks end up cutting this skin AV in half, as against usual AV, so half of the damage that would have normally gotten through(round up) ends up being taken by the protected individual as stun damage. AR bonuses, if any, are applied again, to this skin AV, and will also result in some stun damage being inflicted on the protected individual.

For example, say a warrior in plate(AV 8) with 0 toughness has stoneskin. He is hit by a giant’s greatsword, which is a huge weapon(+2 AR) and does 3d10+10(with an additional +3 AR because 2 handed weapons get a +1 AR, and this weapon is both 2 handed and 3 times normal size, so it gets +3 AR extra, which when added to the +2 AR for a huge attack, gives a +5 AR total). This attack hits for average damage, or 27 points. Normally, the armor the warrior wears removes 8 points, but the giant’s +5 AR bonus means the AV is only 3, with the other 5 AV points reducing damage it would have absorbed to stun instead. So, he would have taken 19 real and 5 stun points normally. But the 5 stun would have 1 point as real, because every 4 stun points means 1 of them is real, so the actual damage would normally be 20 real and 4 stun. Now, the stoneskin comes into play. All stun damage is ignored, so the 4 stun does not harm the warrior after all, only the 20 real points ends up doing any harm. The stoneskin gives him a 20 AV against this attack, since 20 points of real damage would get through. Because the AR of the attack is applied again, this stoneskin AV is now only 15, with 5 points only reducing damage to stun. Thus, the stoneskin blocks 15 of the 20 points totally, with 5 getting through as stun. These 5 stun points are actually taken by the warrior, so this attack uses a stoneskin charge, and ends up inflicting 5 stun points on the warrior. 1 of those 5 stun points is real and the other 4 are stun, so it looks like the warrior did suffer actual harm from the huge attack, 1 real and 4 stun points, from the internal rattling he feels after this massive blow hits him. He might also be knocked down, using normal knockdown rules.