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Ability check: A check of 1d20 + the appropriate ability modifier vs. a DC.
Ability modifier: The bonus or penalty associated with a particular ability score.
AC: Armor Class.
Alignment: One of the nine descriptors of morality and ethics: lawful good (LG), neutral good (NG), chaotic good (CG), lawful neutral (LN), neutral (N), chaotic neutral (CN), lawful evil (LE), neutral evil (NE), and chaotic evil (CE).
Armor Class: A number representing a creature's ability to avoid being hit in combat. An opponent's attack roll must equal or exceed the target creature's Armor Class to hit it.
Attack of opportunity: A single extra melee attack per round that a combatant can make when an opponent within reach takes an action that provokes attacks of opportunity.
Blinded: Unable to see. A blinded character suffers a 50% miss chance in combat, loses any Dexterity bonus to AC, moves at half speed, and suffers a ‑4 penalty on Search checks and on most Strength- and Dexterity-based skill checks. Any skill check that relies on vision automatically fails. Opponents of a blinded character gain a +2 bonus to their attack rolls, since they are effectively invisible.
Charisma (Cha): an ability. Charisma measures a character's force of personality, persuasiveness, personal magnetism, ability to lead, and physical attractiveness. It represents actual personal strength, not merely how one is perceived by others in a social setting.
Chaotic evil: A chaotic evil character does whatever his greed, hatred, and lust for destruction drive him to do. He is hot-tempered, vicious, arbitrarily violent, and unpredictable. Chaotic evil is the most dangerous alignment because it represents the destruction not only of beauty and life but of the order on which beauty and life depend.
Chaotic good: A chaotic good character acts as his conscience directs him with little regard for what others expect of him. He makes his own way, but he's kind and benevolent. Chaotic good is the best alignment you can be because it combines a good heart with a free spirit.
Chaotic neutral: A chaotic neutral character follows his whims. He is an individualist first and last. Chaotic neutral is the best alignment you can be because it represents true freedom both from society's restrictions and from a do-gooder's zeal.
Constitution (Con): An ability. Constitution represents a character's health and stamina.
Dazed: Unable to act normally. A dazed character can take no actions, but can defend against attacks normally.
Dazzled: Unable to see well because of over stimulation of the eyes. A dazzled creature suffers a –1 penalty on attack rolls until the effect ends.
DC: Difficulty Class.
Deafened: Unable to hear. A deafened character suffers a –4 penalty to initiative, automatically fails Listen checks, and has a 20% chance of spell failure when casting spells with verbal components.
Dexterity (Dex): An ability. Dexterity measures hand-eye coordination, agility, reflexes, and balance.
Difficulty Class (DC): The target number that a player must meet or beat for a check or saving throw to succeed.
Entangled: Entanglement impedes movement, but does not entirely prevent it unless the bonds are anchored to an immobile object or tethered by an opposing force. An entangled creature moves at half speed, cannot run or charge, and suffers a –2 penalty to attack rolls and a –4 penalty to its effective Dexterity score.
Exhausted: Tired to the point of significant impairment. A fatigued character becomes exhausted by doing something else that would normally cause fatigue. An exhausted character moves at half normal speed and suffers an effective ability decrease of –6 to both Strength and Dexterity. After 1 hour of complete rest, an exhausted character becomes fatigued.
Extraordinary ability (Ex): A nonmagical special ability (as opposed to a spell-like or supernatural ability).
Fatigued: Tired to the point of impairment. A fatigued character can neither run nor charge and suffers an effective ability decrease of –2 to both Strength and Dexterity. After 8 hours of complete rest, fatigued characters are back to normal.
Feat: A quality or special ability of a character.
Flat-footed: Especially vulnerable to attacks at the beginning of a battle. Characters are flat-footed until their first turns in the initiative cycle. Flat-footed creatures cannot use their Dexterity bonuses to AC or make attacks of opportunity.
Fortitude save: A type of saving throw, related to a character's ability to withstand damage thanks to his physical stamina.
Frightened: Fearful of a creature, situation, or object. Frightened creatures flee from the source of their fear as best they can. If unable to flee, they may fight, but suffer a –2 morale penalty to all their attack rolls, weapon damage rolls, and saving throws.
Hit points (hp): A measure of character health or object integrity. Damage decreases current hit points, and lost hit points return with healing or natural recovery. A character's hit point total increases permanently with additional experience and/or permanent increases in Constitution, or temporarily through the use of various special abilities, spells, magic items, or magical effects (see temporary hit points and effective hit point increase).
Hp: Hit points.
Incorporeal: Having no physical body. Incorporeal creatures are immune to all nonmagical attack forms. They can be harmed only by other incorporeal creatures, +1 or better magical weapons, spells, spell-like effects, or supernatural effects. Even when struck by spells, magical effects, or magic weapons, however, they have a 50% chance to ignore any damage from a corporeal source. In addition, rogues cannot employ sneak attacks against incorporeal beings, since such opponents have no vital areas to target. An incorporeal creature has no natural armor bonus, but does have a deflection bonus equal to its Charisma modifier or +1, whichever is greater. Such creatures can pass through solid objects at will, but not through force effects. Therefore, their attacks negate the bonuses provided by natural armor, armor, and shields, but deflection bonuses and force effects (such as mage armor) work normally against them. Incorporeal creatures move silently, so they cannot be heard with Listen checks unless they wish it.
Intelligence (Int): An ability. Intelligence determines how well a character learns and reasons.
Lawful evil: A lawful evil villain methodically takes what he wants within the limits of his code of conduct without regard to whom it hurts. Lawful evil is the most dangerous alignment because it represents methodical, intentional, and frequently successful evil.
Lawful good: A lawful good character acts as a good person is expected or required to act. Lawful good is the best alignment you can be because it combines honor and compassion.
Lawful neutral: A lawful neutral character acts as law, tradition, or a personal code directs her. Order and organization are paramount to her. Lawful neutral is the best alignment you can be because it means you are reliable and honorable without being a zealot.
Masterwork: Exceptionally well-made, generally adding +1 to attack rolls (if the item is a weapon), reducing the armor check penalty by 1 (if the item is armor), or adding +2 to relevant skill checks (if the item is a tool). A masterwork weapon's bonus to attack rolls does not stack with enhancement bonuses.
Melee attack roll: 1d20 + base attack bonus + Strength modifier + size modifier. The attack hits if the result is at least as high as the target's Armor Class.
Nauseated: Experiencing stomach distress. Nauseated creatures are unable to attack, cast spells, concentrate on spells, or do anything else requiring attention. The only action such a character can take is a single move (or move-equivalent action) per turn.
True neutral: A "true" neutral character does what seems to be a good idea. She doesn't feel strongly one way or the other when it comes to good vs. evil or law vs. chaos. Most neutrality is a lack of conviction or bias rather than a commitment to neutrality. Some neutral characters, on the other hand, commit themselves philosophically to neutrality. They see good, evil, law, and chaos as prejudices and dangerous extremes. They advocate the middle way of neutrality as the best, most balanced road in the long run. Neutral is the best alignment you can be because it means you act naturally, without prejudice or compulsion.
Neutral evil: A neutral evil villain does whatever she can get away with. Neutral evil is the most dangerous alignment because it represents pure evil without honor and without variation.
Neutral good: A neutral good character does the best that a good person can do. Neutral good is the best alignment you can be because it means doing what is good without bias toward or against order.
Nonintelligent: Lacking an Intelligence score. Mind-affecting spells do not affect nonintelligent creatures.
Panicked: A panicked creature must drop anything it holds and flee at top speed from the source of its fear, as well as any other dangers it encounters, along a random path. In addition, the creature suffers a –2 morale penalty on saving throws. If cornered, a panicked creature cowers and does not attack, typically using the total defense action in combat.
Paralyzed: Unable to move or act physically. Paralyzed characters have effective Dexterity and Strength scores of 0 and are helpless.
Petrified: Turned to stone. Petrified characters cannot move or take actions of any kind, and they have effective Strength and Dexterity scores of 0. They are completely unaware of what occurs around them, since all of their senses have ceased to operate. If a petrified character cracks or breaks, but the broken pieces are joined with the body as it returns to flesh, the character is unharmed. Otherwise, the DM must assign some amount of permanent hit point loss and/or debilitation.
Prone: Lying on the ground. An attacker who is prone has a –4 penalty to melee attack rolls and cannot use a ranged weapon (except for a crossbow). Melee attacks against a prone defender have a +4 bonus, and ranged attacks against a prone character have a –4 penalty.
Ranged attack roll: 1d20 + base attack bonus + Dexterity modifier + size modifier + range penalty. The attack hits if the result is at least as high as the target's Armor Class.
Reflex save: A type of saving throw, related to a character's ability to withstand damage thanks to his agility or quick reactions.
Saving throw (save): A roll made to avoid (at least partially) damage or harm.
Skill: an ability or area of knowledge or expertise that can be improved over time.
Spell-like ability (Sp): A special ability with effects that resemble those of a spell. In most cases, a spell-like ability works just like the spell of the same name.
Staggered: Having nonlethal damage equal to current hit points. Staggered characters can only take partial actions. Characters are no longer staggered once their current hit points exceed their nonlethal damage.
Strength (Str): Strength measures a character's muscle and physical power.
Stunned: A stunned creature can't take actions and loses any positive Dexterity modifier to AC. Each attacker gains a +2 bonus to attack rolls against that creature. In addition, stunned characters immediately drop anything they are holding.
Nonlethal damage: Non lethal damage typically resulting from an unarmed attack, an armed attack delivered with intent to subdue, a forced march, or a debilitating condition such as heat or starvation.
Supernatural ability (Su): A magical power that produces a particular effect, as opposed to a natural, extraordinary, or spell-like ability. Using a supernatural ability generally does not provoke an attack of opportunity. Supernatural abilities are not subject to dispelling, disruption, or spell resistance. However, they do not function in areas where magic is suppressed or negated, such as inside an antimagic field.
Take 10: To reduce the chances of failure on certain skill checks by assuming an average die roll result (10 on a 1d20 roll).
Take 20: To greatly reduce the chances of failure for certain skill checks by assuming that a character makes sufficient retries to obtain the maximum possible check result (as if a 20 were rolled on 1d20).
Will save: A type of saving throw, related to a character's ability to withstand damage thanks to his mental toughness.
Wisdom (Wis): An ability. Wisdom describes a character's willpower, common sense, perception, and intuition. While Intelligence represents one's ability to analyze information, Wisdom is more related to being in tune with and aware of one's surroundings.