Your Armor Class (AC) represents how hard it is for opponents to land a solid, damaging blow on you. It's the attack roll result that an opponent needs to achieve to hit you. Your AC is equal to the following:
10 + armor bonus + shield bonus + Dexterity modifier + size modifier
Note that armor limits your Dexterity bonus, so if you're wearing armor, you might not be able to apply your whole Dexterity bonus to your AC.
Sometimes you can't use your Dexterity bonus (if you have one). If you can't react to a blow, you can't use your Dexterity bonus to AC. (If you don't have a Dexterity bonus, nothing happens.)
Many other factors modify your AC.
Enhancement effects make your armor better.
Magical deflection effects ward off attacks and improve your AC.
Natural armor improves your AC.
Some other AC bonuses represent actively avoiding blows. These bonuses are called dodge bonuses. Any situation that denies you your Dexterity bonus also denies you dodge bonuses. (Wearing armor, however, does not limit these bonuses the way it limits a Dexterity bonus to AC.) Unlike most sorts of bonuses, dodge bonuses stack with each other.
Your attack bonus with a melee weapon is:
Base attack bonus + Strength modifier + size modifier
With a ranged weapon, your attack bonus is:
Base attack bonus + Dexterity modifier + size modifier + range penalty
|Attack Roll||Combat||An attack roll represents your attempt to strike your opponent on your turn in a round. When you make an attack roll, you roll a d20 and add your attack bonus. (Other modifiers may also apply to this roll.) If your result equals or beats the target's Armor Class, you hit and deal damage. Automatic Misses and Hits: A natural 1 (the d20 comes up 1) on an attack roll is always a miss. A natural 20 (the d20 comes up 20) is always a hit. A natural 20 is also a threat—a possible critical hit.|
|Attacks of Opportunity||Combat||
Sometimes a combatant in a melee lets her guard down. In this case, combatants near her can take advantage of her lapse in defense to attack her for free. These free attacks are called attacks of opportunity.
You threaten all squares into which you can make a melee attack, even when it is not your action. Generally, that means everything in all squares adjacent to your space (including diagonally). An enemy that takes certain actions while in a threatened square provokes an attack of opportunity from you. If you're unarmed, you don't normally threaten any squares and thus can't make attacks of opportunity.
Most creatures of Medium or smaller size have a reach of only 5 feet. This means that they can make melee attacks only against creatures up to 5 feet (1 square) away. However, Small and Medium creatures wielding reach weapons threaten more squares than a typical creature. In addition, most creatures larger than Medium have a natural reach of 10 feet or more.
Provoking an Attack of Opportunity
Two kinds of actions can provoke attacks of opportunity: moving out of a threatened square and performing an action within a threatened square.
Moving out of a threatened square usually provokes an attack of opportunity from the threatening opponent. There are two common methods of avoiding such an attack—the 5-foot-step and the withdraw action.
Performing a Distracting Act
Some actions, when performed in a threatened square, provoke attacks of opportunity as you divert your attention from the battle. Table: Actions in Combat notes many of the actions that provoke attacks of opportunity.
Remember that even actions that normally provoke attacks of opportunity may have exceptions to this rule.
Making an Attack of Opportunity
An attack of opportunity is a single melee attack, and you can only make one per round. You don't have to make an attack of opportunity if you don't want to.
An experienced character gets additional regular melee attacks (by using the full attack action), but at a lower attack bonus. You make your attack of opportunity, however, at your normal attack bonus—even if you've already attacked in the round.
An attack of opportunity "interrupts" the normal flow of actions in the round. If an attack of opportunity is provoked, immediately resolve the attack of opportunity, then continue with the next character's turn (or complete the current turn, if the attack of opportunity was provoked in the midst of a character's turn).
Combat Reflexes and Additional Attacks of Opportunity
If you have the Combat Reflexes feat you can add your Dexterity modifier to the number of attacks of opportunity you can make in a round. This feat does not let you make more than one attack for a given opportunity, but if the same opponent provokes two attacks of opportunity from you, you could make two separate attacks of opportunity (since each one represents a different opportunity). Moving out of more than one square threatened by the same opponent in the same round doesn't count as more than one opportunity for that opponent. All these attacks are at your full normal attack bonus.
|Concealment||Combat||To determine whether your target has concealment from your ranged attack, choose a corner of your square. If any line from this corner to any corner of the target's square passes through a square or border that provides concealment, the target has concealment. When making a melee attack against an adjacent target, your target has concealment if his space is entirely within an effect that grants concealment. When making a melee attack against a target that isn't adjacent to you use the rules for determining concealment from ranged attacks. In addition, some magical effects provide concealment against all attacks, regardless of whether any intervening concealment exists. You can use concealment to make a Hide check. Without concealment, you usually need cover to make a Hide check.|
|Concealment Miss Chance||Combat||Concealment gives the subject of a successful attack a 20% chance that the attacker missed because of the concealment. If the attacker hits, the defender must make a miss chance percentile roll to avoid being struck. Multiple concealment conditions do not stack.|
|Cover||Combat||To determine whether your target has cover from your ranged attack, choose a corner of your square. If any line from this corner to any corner of the target's square passes through a square or border that blocks line of effect or provides cover, or through a square occupied by a creature, the target has cover (+4 to AC). When making a melee attack against an adjacent target, your target has cover if any line from your square to the target's square goes through a wall (including a low wall). When making a melee attack against a target that isn't adjacent to you (such as with a reach weapon), use the rules for determining cover from ranged attacks. A low obstacle (such as a wall no higher than half your height) provides cover, but only to creatures within 30 feet (6 squares) of it. The attacker can ignore the cover if he's closer to the obstacle than his target. You can't execute an attack of opportunity against an opponent with cover relative to you. Cover grants you a +2 bonus on Reflex saves against attacks that originate or burst out from a point on the other side of the cover from you. Note that spread effects can extend around corners and thus negate this cover bonus. You can use cover to make a Hide check. Without cover, you usually need concealment to make a Hide check. Creatures, even your enemies, can provide you with cover against ranged attacks, giving you a +4 bonus to AC. However, such soft cover provides no bonus on Reflex saves, nor does soft cover allow you to make a Hide check. Any creature with a space larger than 5 feet (1 square) determines cover against melee attacks slightly differently than smaller creatures do. Such a creature can choose any square that it occupies to determine if an opponent has cover against its melee attacks. Similarly, when making a melee attack against such a creature, you can pick any of the squares it occupies to determine if it has cover against you. In some cases, cover may provide a greater bonus to AC and Reflex saves. In such situations the normal cover bonuses to AC and Reflex saves can be doubled (to +8 and +4, respectively). A creature with this improved cover effectively gains improved evasion against any attack to which the Reflex save bonus applies. Furthermore, improved cover provides a +10 bonus on Hide checks.|
When your attack succeeds, you deal damage. The type of weapon used determines the amount of damage you deal. Effects that modify weapon damage apply to unarmed strikes and the natural physical attack forms of creatures.
Damage reduces a target's current hit points.
If penalties reduce the damage result to less than 1, a hit still deals 1 point of damage.
When you hit with a melee or thrown weapon, including a sling, add your Strength modifier to the damage result. A Strength penalty, but not a bonus, applies on attacks made with a bow that is not a composite bow.
When you deal damage with a weapon in your off hand, you add only ½ your Strength bonus.
Wielding a Weapon Two-Handed
When you deal damage with a weapon that you are wielding two-handed, you add 1½ times your Strength bonus. However, you don't get this higher Strength bonus when using a light weapon with two hands.
Sometimes you multiply damage by some factor, such as on a critical hit. Roll the damage (with all modifiers) multiple times and total the results. Note: When you multiply damage more than once, each multiplier works off the original, unmultiplied damage.
Exception: Extra damage dice over and above a weapon's normal damage are never multiplied.
Certain creatures and magical effects can cause temporary ability damage (a reduction to an ability score).
|Determining Awareness||Combat||Sometimes all the combatants on a side are aware of their opponents, sometimes none are, and sometimes only some of them are. Sometimes a few combatants on each side are aware and the other combatants on each side are unaware. Determining awareness may call for Listen checks, Spot checks, or other checks.|
|Flanking||Combat||When making a melee attack, you get a +2 flanking bonus if your opponent is threatened by a character or creature friendly to you on the opponent's opposite border or opposite corner. When in doubt about whether two friendly characters flank an opponent in the middle, trace an imaginary line between the two friendly characters' centers. If the line passes through opposite borders of the opponent's space (including corners of those borders), then the opponent is flanked. Exception: If a flanker takes up more than 1 square, it gets the flanking bonus if any square it occupies counts for flanking. Only a creature or character that threatens the defender can help an attacker get a flanking bonus. Creatures with a reach of 0 feet can't flank an opponent.|
|Flat-Footed||Combat||At the start of a battle, before you have had a chance to act (specifically, before your first regular turn in the initiative order), you are flat-footed. You can't use your Dexterity bonus to AC (if any) while flat-footed. Barbarians and rogues have the uncanny dodge extraordinary ability, which allows them to avoid losing their Dexterity bonus to AC due to being flat-footed. A flat-footed character can't make attacks of opportunity.|
|Fortitude||Combat||These saves measure your ability to stand up to physical punishment or attacks against your vitality and health. Apply your Constitution modifier to your Fortitude saving throws.|
|Hit Points||Combat||When your hit point total reaches 0, you're disabled. When it reaches -1, you're dying. When it gets to -10, you're dead.|
|Ignoring Concealment||Combat||Concealment isn't always effective. A shadowy area or darkness doesn't provide any concealment against an opponent with darkvision. Characters with low-light vision can see clearly for a greater distance with the same light source than other characters. Although invisibility provides total concealment, sighted opponents may still make Spot checks to notice the location of an invisible character. An invisible character gains a +20 bonus on Hide checks if moving, or a +40 bonus on Hide checks when not moving (even though opponents can't see you, they might be able to figure out where you are from other visual clues).|
|Inaction||Combat||Even if you can't take actions, you retain your initiative score for the duration of the encounter.|
|Initiative Checks||Combat||At the start of a battle, each combatant makes an initiative check. An initiative check is a Dexterity check. Each character applies his or her Dexterity modifier to the roll. Characters act in order, counting down from highest result to lowest. In every round that follows, the characters act in the same order (unless a character takes an action that results in his or her initiative changing; see Special Initiative Actions). If two or more combatants have the same initiative check result, the combatants who are tied act in order of total initiative modifier (highest first). If there is still a tie, the tied characters should roll again to determine which one of them goes before the other.|
|Mounted Combat||Combat||Horses in Combat Heavy warhorses, light warhorses and warponies can serve readily as combat steeds. Light horses, ponies, and heavy horses, however, are frightened by combat. If you don't dismount, you must make a DC 20 Ride check each round as a move action to control such a horse. If you succeed, you can perform a standard action after the move action. If you fail, the move action becomes a full round action and you can't do anything else until your next turn. Your mount acts on your initiative count as you direct it. You move at its speed, but the mount uses its action to move. A horse (not a pony) is a Large creature and thus takes up a space 10 feet (2 squares) across. For simplicity, assume that you share your mount's space during combat. Combat while Mounted With a DC 5 Ride check, you can guide your mount with your knees so as to use both hands to attack or defend yourself. This is a free action. When you attack a creature smaller than your mount that is on foot, you get the +1 bonus on melee attacks for being on higher ground. If your mount moves more than 5 feet, you can only make a single melee attack. Essentially, you have to wait until the mount gets to your enemy before attacking, so you can't make a full attack. Even at your mount's full speed, you don't take any penalty on melee attacks while mounted. If your mount charges, you also take the AC penalty associated with a charge. If you make an attack at the end of the charge, you receive the bonus gained from the charge. When charging on horseback, you deal double damage with a lance. You can use ranged weapons while your mount is taking a double move, but at a -4 penalty on the attack roll. You can use ranged weapons while your mount is running (quadruple speed), at a -8 penalty. In either case, you make the attack roll when your mount has completed half its movement. You can make a full attack with a ranged weapon while your mount is moving. Likewise, you can take move actions normally Casting Spells while Mounted You can cast a spell normally if your mount moves up to a normal move (its speed) either before or after you cast. If you have your mount move both before and after you cast a spell, then you're casting the spell while the mount is moving, and you have to make a Concentration check due to the vigorous motion (DC 10 + spell level) or lose the spell. If the mount is running (quadruple speed), you can cast a spell when your mount has moved up to twice its speed, but your Concentration check is more difficult due to the violent motion (DC 15 + spell level). If Your Mount Falls in Battle If your mount falls, you have to succeed on a DC 15 Ride check to make a soft fall and take no damage. If the check fails, you take 1d6 points of damage. If You Are Dropped If you are knocked unconscious, you have a 50% chance to stay in the saddle (or 75% if you're in a military saddle). Otherwise you fall and take 1d6 points of damage. Without you to guide it, your mount avoids combat.|
Dealing Nonlethal Damage
Certain attacks deal nonlethal damage. Other effects, such as heat or being exhausted, also deal nonlethal damage. When you take nonlethal damage, keep a running total of how much you've accumulated. Do not deduct the nonlethal damage number from your current hit points. It is not "real" damage. Instead, when your nonlethal damage equals your current hit points, you're staggered, and when it exceeds your current hit points, you fall unconscious. It doesn't matter whether the nonlethal damage equals or exceeds your current hit points because the nonlethal damage has gone up or because your current hit points have gone down.
Nonlethal Damage with a Weapon that Deals Lethal Damage
You can use a melee weapon that deals lethal damage to deal nonlethal damage instead, but you take a -4 penalty on your attack roll.
Lethal Damage with a Weapon that Deals Nonlethal Damage
You can use a weapon that deals nonlethal damage, including an unarmed strike, to deal lethal damage instead, but you take a -4 penalty on your attack roll.
Staggered and Unconscious
When your nonlethal damage equals your current hit points, you're staggered. You can only take a standard action or a move action in each round. You cease being staggered when your current hit points once again exceed your nonlethal damage.
When your nonlethal damage exceeds your current hit points, you fall unconscious. While unconscious, you are helpless.
Spellcasters who fall unconscious retain any spellcasting ability they had before going unconscious.
Healing Nonlethal Damage
You heal nonlethal damage at the rate of 1 hit point per hour per character level.
When a spell or a magical power cures hit point damage, it also removes an equal amount of nonlethal damage.
|Reflex||Combat||These saves test your ability to dodge area attacks. Apply your Dexterity modifier to your Reflex saving throws.|
|Saving Throws||Combat||Generally, when you are subject to an unusual or magical attack, you get a saving throw to avoid or reduce the effect. Like an attack roll, a saving throw is a d20 roll plus a bonus based on your class, level, and an ability score. Your saving throw modifier is: Base save bonus + ability modifier|
|Speed||Combat||Your speed tells you how far you can move in a round and still do something, such as attack or cast a spell. Your speed depends mostly on your race and what armor you're wearing. Dwarves, gnomes, and halflings have a speed of 20 feet (4 squares), or 15 feet (3 squares) when wearing medium or heavy armor (except for dwarves, who move 20 feet in any armor). Humans, elves, half-elves, and half-orcs have a speed of 30 feet (6 squares), or 20 feet (4 squares) in medium or heavy armor. If you use two move actions in a round (sometimes called a "double move" action), you can move up to double your speed. If you spend the entire round to run all out, you can move up to quadruple your speed (or triple if you are in heavy armor).|
|Surprise||Combat||When a combat starts, if you are not aware of your opponents and they are aware of you, you're surprised.|
|Surprise Round||Combat||If some but not all of the combatants are aware of their opponents, a surprise round happens before regular rounds begin. Any combatants aware of the opponents can act in the surprise round, so they roll for initiative. In initiative order (highest to lowest), combatants who started the battle aware of their opponents each take a standard action during the surprise round. You can also take free actions during the surprise round. If no one or everyone is surprised, no surprise round occurs.|
|Temporary Hit Points||Combat||Certain effects give a character temporary hit points. When a character gains temporary hit points, note his current hit point total. When the temporary hit points go away the character's hit points drop to his current hit point total. If the character's hit points are below his current hit point total at that time, all the temporary hit points have already been lost and the character's hit point total does not drop further. When temporary hit points are lost, they cannot be restored as real hit points can be, even by magic. Increases in Constitution Score and Current Hit Points An increase in a character's Constitution score, even a temporary one, can give her more hit points (an effective hit point increase), but these are not temporary hit points. They can be restored and they are not lost first as temporary hit points are.|
|Total Concealment||Combat||If you have line of effect to a target but not line of sight he is considered to have total concealment from you. You can't attack an opponent that has total concealment, though you can attack into a square that you think he occupies. A successful attack into a square occupied by an enemy with total concealment has a 50% miss chance (instead of the normal 20% miss chance for an opponent with concealment). You can't execute an attack of opportunity against an opponent with total concealment, even if you know what square or squares the opponent occupies.|
|Total Cover||Combat||If you don't have line of effect to your target he is considered to have total cover from you. You can't make an attack against a target that has total cover.|
|Touch Attacks||Combat||Some attacks disregard armor, including shields and natural armor. In these cases, the attacker makes a touch attack roll (either ranged or melee). When you are the target of a touch attack, your AC doesn't include any armor bonus, shield bonus, or natural armor bonus. All other modifiers, such as your size modifier, Dexterity modifier, and deflection bonus (if any) apply normally.|
|Unaware Combatants||Combat||Combatants who are unaware at the start of battle don't get to act in the surprise round. Unaware combatants are flat-footed because they have not acted yet, so they lose any Dexterity bonus to AC.|
|Vile Damage||Combat||Vile Damage, like regular damage, results in the loss of hit points or ability score points. Unlike regular damage, vile damage can only be healed by magic cast within the area of a consecrate or hallow spell. Vile damage represents such a evil violation to a character's body or soul that only in a holy place can healing magic repair the damage|
|Will||Combat||These saves reflect your resistance to mental influence as well as many magical effects. Apply your Wisdom modifier to your Will saving throws.|