TEXT: D20 Combat Rules 
   
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  COMBAT BASICS 
  Special Terms 
  Face: How wide a face a combatant 
  presents in combat. Face is essentially the 
  border between the square or rectangular 
  space that a combatant occupies and the 
  space next to it. These faces are abstract, 
  not "front, back, left, and right," because 
  combatants are constantly moving and 
  turning in battle. Unless a combatant is 
  immobile, it practically doesn't have a 
  front or a left side—at least not one that 
  can be identified on the tabletop.  
  Flanking: If a combatant is making a 
  melee attack against an opponent, and an 
  ally directly opposite the combatant is 
  threatening the opponent, the combatant 
  and the combatant's ally flank the 
  opponent. A combatant gains a +2 
  flanking bonus on the attack roll. A rogue 
  in this position can also sneak attack the 
  target. The ally must be on the other side 
  of the opponent, so that the opponent is 
  directly between the combatant and the 
  ally.  
  Flat-Footed: At the start of a battle each 
  combatant is flat-footed. A combatant 
  can't use a Dexterity bonus to AC (if any) 
  while flat-footed. A flat-footed combatant 
  can't make attacks of opportunity.  
  Initiative Check: At the start of a battle, 
  each combatant makes a single initiative 
  check. An initiative check is a Dexterity 
  check. If two or more combatants have the 
  same 
  initiative 
  check 
  result, 
  the 
  combatants who are tied go in order of 
  Dexterity (highest first). If there is still a 
  tie, flip a coin.  
  Touch Attack: Touch attacks come in two 
  types: melee touch attacks and ranged 
  touch attacks. A combatant can score 
  critical hits with either type of attack. A 
  combatant's opponent's AC against a touch 
  attack does not include any armor bonus, 
  shield bonus, or natural armor bonus. The 
  target's size modifier, Dexterity modifier, 
  and deflection bonus (if any) all apply 
  normally.  
  Table: Size Modifiers 
  Size           
  AC/Attack Modifier 
  Fine             
  +8 
  Diminutive       
  +4 
  Tiny             
  +2 
  Small            
  +1 
  Medium            
  0 
  Large            
  -1 
  Huge             
  -2 
  Gargantuan       
  -4 
  Colossal         
  -8 
  Apply this modifier to the attack rolls and 
  AC values of combatants, unless the value 
  has not already been precalculated to 
  include this modifier. 
  Combat Sequence 
  Step One: The DM determines which 
  combatants are aware of their opponents at 
  the start of the battle. If some but not all of 
  the combatants are aware of their 
  opponents, a surprise round happens 
  before 
  regular 
  rounds 
  begin. 
  The 
  combatants 
  who 
  are 
  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 partial action during the 
  surprise round. Combatants who were 
  unaware do not get to act in the surprise 
  round. If no one or everyone starts the 
  battle aware, there is no surprise round.  
  Step Two: Combatants who have not yet 
  rolled initiative do so.  
  Step Three: Combatants act in initiative 
  order.  
  
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  Step Four: When everyone has had a turn, 
  the combatant with the highest initiative 
  acts again, and steps 4 and 5 repeat until 
  combat ends.  
  Attacks of Opportunity 
  Threatened Area: A combatant threatens 
  the area into which it can make a melee 
  attack, even when it is not a combatant's 
  action. An enemy that takes certain actions 
  while in a threatened area may provoke an 
  attack of opportunity from a combatant.  
  A combatant normally threatens all 
  adjacent spaces. "Reach weapons" and 
  "natural reach" can change the threatened 
  area.  
  Provoking an Attack of Opportunity by 
  Moving: If a combatant moves through 
  (not simply into) or out of a threatened 
  area, a combatant usually provokes an 
  attack of opportunity.  
  If all a combatant does is take a normal 
  move or a double move (not a run), the 
  space that the combatant started out in is 
  not considered threatened.  
  If a combatant's entire move for the round 
  is 5 feet the 5 foot move does not provoke 
  an attack of opportunity.  
  Provoking an Attack of Opportunity by 
  Taking an Action: A combatant taking 
  some kinds actions provokes attacks of 
  opportunity, as described in the rules for 
  each action type.  
  Making an Attack of Opportunity: An 
  attack of opportunity is a single melee 
  attack, and a combatant can only make one 
  per round. The combatant does not have to 
  make an attack of opportunity if the 
  combatant doesn't want to. A combatant 
  can make the attack of opportunity at a 
  combatant's normal attack bonus - even if 
  the combatant has already attacked this 
  round.  
  The Combat Round 
  Each round represents about 6 seconds in 
  the game world. Anything a person could 
  reasonably do in 6 seconds, a combatant 
  can do in 1 round.  
  When a combatant's turn comes up in the 
  initiative 
  sequence, 
  that 
  combatant 
  performs his entire round's worth of 
  actions.  
  Effects that last a certain number of rounds 
  end just before the same initiative count 
  that they began on.  
  COMBAT ACTIONS 
  Action Descriptions 
  Name: The name of the action type.  
  [ Type ]: The type of action – not an 
  action, free, partial, move-equivalent, 
  standard or full round.  
  [ AoO ]: Attack of Opportunity: Yes, no or 
  maybe, 
  depending 
  on 
  the 
  action 
  description.  
  Description: A brief description of the 
  action.  
  Action Types 
  Not an Action: Some activities are not 
  even 
  considered 
  free 
  actions. 
  They 
  literally don't take any time at all to do and 
  are considered an inherent part of doing 
  something else.  
  Free Action: A combatant can perform 
  one or more free actions while taking 
  another action normally. However, the 
  DM puts reasonable limits on what a 
  combatant can really do for free.  
  Partial Action: As a general rule, a 
  combatant can do as much with a partial 
  action as a combatant could with a 
  standard action minus a move. Typically, a 
  
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  combatant may take a 5-foot step as part 
  of a partial action.  
  Move-Equivalent 
  Action: 
  Move-
  equivalent actions take the place of 
  movement in a standard action or take the 
  place of an entire partial action. The 
  combatant can normally also take a 5 foot 
  step.  
  Standard Action: A standard action 
  allows a combatant to do something and 
  move a combatant's indicated speed during 
  a combat round. A combatant can move 
  before or after performing the activity of 
  the action.  
  Full-Round Action: A full-round action 
  consumes all a combatant's effort during a 
  round. The only movement a combatant 
  can take during a full- round action is a 5-
  foot step before, during, or after the action. 
  A combatant can also perform free actions. 
  Some full-round actions do not allow a 5-
  foot step.  
  Actions 
  Activate magic item  
  [Standard][AoO: Maybe] 
  Many magic items don't need to be 
  activated. However, certain magic items 
  need to be activated. Activating a magic 
  item is a standard action (unless the item 
  description indicates otherwise).  
  Activating a spell completion item, is the 
  equivalent of casting a spell. It requires 
  concentration and provokes attacks of 
  opportunity. A combatant loses the spell if 
  the combatant's concentration is broken, 
  and the combatant can attempt to activate 
  the item while on the defensive, as with a 
  spell.  
  Activating a spell trigger, command word, 
  or use-activated item does not require 
  concentration and does not provoke 
  attacks of opportunity.  
  Aid another  
  [Standard][AoO: No] 
  If a combatant threatens an opponent with 
  which an ally is engaged in melee combat, 
  the combatant can attempt to aid the ally 
  as a standard action. The combatant makes 
  an attack roll against AC 10. If the 
  combatant succeeds, the combatant's ally 
  gains either a +2 circumstance bonus to 
  attack that opponent or a +2 circumstance 
  bonus to AC against that opponent (the 
  combatant's choice).  
  Attack (melee)  
  [Standard][AoO: No] 
  The combatant attacks an opponent in a 
  space that combatant threatens. The attack 
  roll is:  
  d20 + Attack modifiers vs. AC of target  
  Attack 
  modifiers 
  consist 
  of 
  the 
  combatant's base attack bonus, size 
  adjustment, strength adjustment, and any 
  other bonuses that apply to the attack roll.  
  A natural 1 on the d20 is always a miss, 
  and a natural 20 on the d20 is always a hit.  
  If the modified attack roll is equal to or 
  greater than the AC of the target, the 
  attack is successful. The attack may also 
  be a Threat. See Critical Hits and Dealing 
  Damage, below, for more details.  
  If the combatant is attacking an armed 
  opponent while unarmed, the combatant 
  provokes 
  an 
  immediate 
  attack 
  of 
  opportunity from the target which is 
  resolved before the combatant's attack. 
  Note that under certain circumstances, a 
  combatant attacking without a weapon is 
  still considered "armed".  
  A 
  combatant 
  can 
  choose 
  to 
  fight 
  defensively when taking the attack action. 
  If a combatant does so, the combatant 
  takes a -4 penalty on all attacks in a round 
  
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  to gain a +2 dodge bonus to AC for the 
  same round.  
  Attack (ranged)  
  [Standard][AoO: Yes] 
  The combatant attacks an opponent in line 
  of sight to the combatant, within range of 
  the ranged weapon being used. A target is 
  in line of sight if no obstructions between 
  the combatant and the target grant 100% 
  cover. The maximum range for a thrown 
  weapon is five range increments, for 
  projectile 
  weapons 
  it 
  is 
  ten 
  range 
  increments. The attack roll is:  
  d20 + Attack modifiers vs. AC of target  
  Attack 
  modifiers 
  consist 
  of 
  the 
  combatant's base attack bonus, size 
  adjustment, dexterity adjustment, and any 
  other bonuses that apply to the attack roll. 
  Each range increment of distance between 
  the combatant and the target after the first 
  will impose a penalty, per the weapon 
  description.  
  A natural 1 on the d20 is always a miss, 
  and a natural 20 on the d20 is always a hit.  
  If the modified attack roll is equal to or 
  greater than the AC of the target, the 
  attack is successful. The attack may also 
  be a Threat. See Critical Hits and Dealing 
  Damage, below, for more details.  
  If a combatant shoots or throws a ranged 
  weapon at a target that is engaged in melee 
  with an ally, that combatant suffer a -4 
  penalty on it's attack roll. Two combatants 
  are engaged in melee if they are enemies 
  of each other and either threatens the 
  other. (A held, unconscious, or otherwise 
  immobilized combatant is not considered 
  engaged unless he is actually being 
  attacked.)  
  If a combatant's target (or the part of a 
  target a combatant is aiming at, if it's a big 
  target) is at least 10 feet away from the 
  nearest ally, the combatant can avoid the -
  4 penalty, even if the combatant being 
  aimed at is engaged in melee with an ally.  
  A 
  combatant 
  can 
  choose 
  to 
  fight 
  defensively when taking the attack action. 
  If a combatant does so, the combatant 
  takes a -4 penalty on all attacks in a round 
  to gain a +2 dodge bonus to AC for the 
  same round.  
  Bull rush 
  [Standard][AoO: Yes]  
  A combatant can bull rush as an attack 
  action or a charge action.  
  When a combatant bull rushes, the 
  combatant attempts to push an opponent 
  straight back instead of attacking him. A 
  combatant can only bull rush an opponent 
  who is one size category larger than the 
  combatant, the same size, or smaller.  
  Initiating a Bull Rush: First, the 
  combatant moves into the defender's 
  space. Moving in this way provokes an 
  attack of opportunity from each foe that 
  threatens 
  the 
  combatant, 
  probably 
  including the defender. Any attack of 
  opportunity made by anyone other than the 
  defender against the combatant during a 
  bull rush has a 25% chance of accidentally 
  targeting the defender instead, and any 
  attack of opportunity by anyone other than 
  the 
  combatant 
  against 
  the 
  defender 
  likewise has a 25% chance of accidentally 
  targeting the combatant.  
  Second, the combatant and the defender 
  make opposed Strength checks. The 
  combatant adds a +4 bonus for each size 
  category that the combatant is above 
  Medium-size or a -4 penalty for each size 
  category that the combatant is below 
  Medium-size. The combatant gets a +2 
  charge bonus if the Bull Rush is attempted 
  at the end of a Charge. The defender gets a 
  
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  +4 stability bonus if he has more than two 
  legs or is otherwise exceptionally stable.  
  Bull Rush Results: If the combatant beat 
  the defender, the combatant pushes the 
  defender back 5 feet. If the combatant 
  wishes to move with the defender, the 
  combatant can push the defender back up 
  to a distance of an additional 1 foot for 
  each point by which the combatant 
  exceeded the defender's check result. A 
  combatant can't, however, exceed his or 
  her normal movement limit.  
  If the combatant fails to beat the 
  defender's Strength check, the combatant 
  moves 5 feet straight back. If that space is 
  occupied, the combatant falls prone in that 
  space.  
  Cast a quickened spell  
  [Free][AoO: No] 
  Self explanatory.  
  Cast a spell (1-action)  
  [Standard][AoO: Yes] 
  Casting a spell with a casting time of 1 
  action is a standard action. A combatant 
  can move and then cast the spell, or cast 
  the spell and then move.  
  A combatant may attempt to cast a spell 
  while on the defensive. Casting a spell 
  while on the defensive does not provoke 
  an attack of opportunity. It does require a 
  Concentration check (DC 15 + spell level). 
  Failure means that the combatant loses the 
  spell.  
  Cast a spell (full-round)  
  [Full][AoO: Yes] 
  The spell will take effect just before the 
  caster's action in the next round.  
  A combatant can take a 5-foot step before, 
  during, or after casting such a spell, but 
  cannot otherwise move.  
  A combatant may attempt to cast a spell 
  while on the defensive. Casting a spell 
  while on the defensive does not provoke 
  an attack of opportunity. It does require a 
  Concentration check (DC 15 + spell level). 
  Failure means that the combatant loses the 
  spell.  
  Cease concentration on a spell 
  [Free][AoO: No] 
  Self explanatory.  
  Climb  
  [Full][AoO: No] 
  As a full round action, a combatant can 
  climb at one half base speed.  
  Climb 
  [Move Equivalent][AoO: No] 
  As a move equivalent action, a combatant 
  can climb at one quarter base speed.  
  Change form (polymorph self) 
  [Full][AoO: Yes] 
  Per the spell.  
  Change form (shapeshifter)  
  [Standard][AoO: No] 
  Self explanatory.  
  Change form (shapechange) 
  [Free][AoO: No] 
  Self explanatory.  
  Charge 
  [Full][AoO: Yes] 
  The 
  combatant 
  must 
  move 
  before 
  attacking, not after. The combatant must 
  
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  move at least 10 feet and may move up to 
  double base speed. All movement must be 
  in a straight line, with no backing up 
  allowed. The charge stops as soon as the 
  combatant 
  threatens 
  the 
  target. 
  A 
  combatant can't run past the target and 
  attack from another direction.  
  After moving, the combatant may make a 
  single melee attack or a bull rush. The 
  combatant gets a +2 bonus on the attack 
  roll. The combatant also suffers a -2 
  penalty to AC for 1 round.  
  A lance deals double damage if employed 
  by a mounted combatant in a charge.  
  A target can ready certain piercing 
  weapons, setting them to receive charges 
  by using the ready action against receiving 
  a charge. A weapon of this type deals 
  double damage if the readied attack is 
  successful.  
  Concentrate to maintain or 
  redirect a spell  
  [Standard][AoO: No] 
  Anything that could break a combatant's 
  concentration when casting a spell can 
  keep a combatant from concentrating to 
  maintain 
  a 
  spell. 
  If 
  a 
  combatant's 
  concentration breaks, the spell ends.  
  Coup de grace  
  [Full][AoO: Yes] 
  A combatant can use a melee weapon to 
  deliver a coup de grace to a helpless foe. A 
  combatant can also use a bow or 
  crossbow, provided the combatant is 
  adjacent to the target. The attacker 
  automatically hits and scores a critical hit. 
  If the target survives the damage, the 
  target must make a Fortitude save (DC 10 
  + damage dealt) or die.  
  It's overkill, but a rogue also gets her extra 
  sneak attack damage against a helpless foe 
  when delivering a coup de grace.  
  A combatant can't deliver a coup de grace 
  against an opponent that is immune to 
  critical hits, such as a golem.  
  Control a frightened mount  
  [Move Equivalent][AoO: Yes] 
  The combatant must make a Ride check 
  (DC 20) each round to control a mount 
  untrained for war (untrained mounts 
  include light and heavy horses, and 
  ponies). If the check is successful, the 
  combatant can perform a partial action 
  after the check. If the Ride check fails, the 
  check is considered to have been a full-
  round action.  
  Delay  
  [Not an Action][AoO: No]  
  When a combatant delays, the combatant 
  voluntarily reduces it's own initiative 
  result for the rest of the combat. When a 
  combatant's new, lower initiative count 
  comes up later in the same round, the 
  combatant can act normally. A combatant 
  can specify this new initiative result or just 
  wait until some time later in the round and 
  act then, thus fixing the combatant's new 
  initiative 
  count 
  at 
  that 
  point.  
  A combatant can only voluntarily lower its 
  initiative to –10 minus its initiative bonus. 
  When the initiative count reaches –10 
  minus a delaying combatant's initiative 
  bonus, that combatant must act or forfeit 
  any action that round.  
  If multiple combatants are delaying, the 
  one with the highest initiative bonus (or 
  highest Dexterity, in case of a tie) has the 
  advantage. If two or more delaying 
  combatants both want to act on the same 
  initiative count, the one with the highest 
  bonus gets to go first. If two or more 
  
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  delaying combatants are trying to go after 
  the other, the one with the highest 
  initiative bonus gets to go last.  
  Disarm (4) 
  [Varies][AoO: Yes] 
  The combatant and an adjacent target 
  make opposed attack rolls with the their 
  respective weapons. If the weapons are 
  different sizes, the opponent with the 
  larger weapon gets a bonus on the attack 
  roll of +4 per difference in size category. 
  If the target is using a weapon in two 
  hands, he gets an additional +4 bonus. If 
  the combatant beats the target, the target is 
  disarmed. If a combatant attempted the 
  disarm action unarmed, the combatant 
  now has the weapon. Otherwise, it drops 
  to the ground at the target's feet. If the 
  combatant fails, then the target may make 
  an attempt to disarm the combatant as an 
  immediate, free action.  
  Note: A target wearing spiked gauntlets 
  can't be relieved of the gauntlets by a 
  disarm action. A target using a weapon 
  attached to a locked gauntlet gets a +10 
  bonus to any disarm attempt made by an 
  opponent.  
  This action substitutes for a melee attack, 
  not an action. As melee attacks, it can be 
  used once in an attack or charge action, 
  one or more times in a full attack action, 
  or even as an attack of opportunity.  
  Dismiss a spell  
  [Standard][AoO: No] 
  Self explanatory.  
  Dive Attack  
  [Full][AoO: Yes] 
  Creatures that fly can make dive attacks.  
  A dive attack works just like a charge, but 
  the diving creature must move a minimum 
  of 30 feet. It can make only claw attacks, 
  but these deal double damage.  
  Double move 
  [Full][Varies] 
  A combatant can move up to double base 
  speed.  
  The space where a combatant begins the 
  move is not considered threatened, and 
  therefore enemies do not get attacks of 
  opportunity for a combatant's move from 
  that space.  
  Draw a weapon  
  [Move Equivalent][AoO: No] 
  If a combatant has a base attack bonus of 
  +1 or higher, a combatant can combine 
  one of these actions with a regular move. 
  If a combatant has the Two-Weapon 
  Fighting feat, a combatant can draw two 
  light or one-handed weapons in the time it 
  would normally take a combatant to draw 
  one.  
  Drop an item  
  [Free][AoO: No] 
  The item falls to the floor in the same 
  space as the combatant.  
  Drop to the floor  
  [Free][AoO: No] 
  The combatant is considered to be prone.  
  Escape from a net  
  [Full][AoO: Yes] 
  The description of the net involved will 
  include information on how to determine 
  if an escape attempt has been successful or 
  not.  
   
   
  
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  Extinguish flames  
  [Full][AoO: No] 
  This action will extinguish small fires on 
  equipment, furniture, or the combatant's 
  person. Larger blazes will require the use 
  of water, sand, or some other material to 
  snuff the flames.  
  Feint  
  [Standard][AoO: No] 
  This is a specialized use of the Bluff skill. 
  See the Bluff skill for more details.  
  Full attack 
  [Full][AoO: No] 
  If a combatant gets more than one attack 
  per action, the combatant must use the full 
  attack action to use those additional 
  attacks. A combatant does not need to 
  specify the targets of a the attacks ahead of 
  time. A combatant can see how the earlier 
  attacks turn out before assigning the later 
  ones.  
  The combatant may take a 5 ft. step 
  before, after, or between the attacks.  
  If a combatant gets multiple attacks based 
  on a combatant's base attack bonus, the 
  combatant must make the attacks in order 
  from highest bonus to lowest.  
  Deciding between an Attack or a Full 
  Attack Action: After a combatant's first 
  attack, if the combatant has not yet taken a 
  5-foot step, a combatant can decide to 
  move instead of making a combatant's 
  remaining attacks.  
  The combatant uses each attack to attack 
  an opponent in a space that combatant 
  threatens. The attack roll is:  
  d20 + Attack modifiers vs. AC of target  
  Attack 
  modifiers 
  consist 
  of 
  the 
  combatant's base attack bonus, size 
  adjustment, strength adjustment, and any 
  other bonuses that apply to the attack roll.  
  A natural 1 on the d20 is always a miss, 
  and a natural 20 on the d20 is always a hit.  
  If the modified attack roll is equal to or 
  greater than the AC of the target, the 
  attack is successful. The attack may also 
  be a Threat. See Critical Hits and Dealing 
  Damage, below, for more details.  
  If the combatant is attacking an armed 
  opponent while unarmed, the combatant 
  provokes 
  an 
  immediate 
  attack 
  of 
  opportunity from the target which is 
  resolved before the combatant's attack. 
  Note that under certain circumstances, a 
  combatant attacking without a weapon is 
  still considered "armed".  
  A 
  combatant 
  can 
  choose 
  to 
  fight 
  defensively when taking the full attack 
  action. If a combatant does so, the 
  combatant takes a -4 penalty on all attacks 
  in a round to gain a +2 dodge bonus to AC 
  for the same round.  
  Grapple 
  [Varies][AoO: Yes] 
  Grappling means wrestling and struggling 
  hand-to-hand.  
  Repeatedly in a grapple, a combatant 
  needs to make opposed grapple checks 
  against an opponent. A grapple check is 
  something like a melee attack roll.  
  A combatant's attack bonus on a grapple 
  check is: Base attack bonus + Strength 
  modifier + special size modifier  
  Special Size Modifier: The special size 
  modifier for a grapple check is as follows: 
  Colossal +16, Gargantuan +12, Huge +8, 
  Large +4, Medium-size +0, Small –4, Tiny 
  – 8, Diminutive –12, Fine –16. Use this 
  number in place of the normal size 
  modifier a combatant uses when making 
  an attack roll.  
  
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  A combatant provokes an attack of 
  opportunity from the target the combatant 
  is trying to grapple. If the attack of 
  opportunity deals the combatant damage, 
  the combatant fails to start the grapple.  
  To start a grapple, a combatant first needs 
  to grab and hold a combatant's target. 
  Attempting to start a grapple is the 
  equivalent of making a melee attack. If a 
  combatant gets multiple attacks in a round, 
  a combatant can attempt to start a grapple 
  multiple times (at successively lower base 
  attack bonuses). A monk can use his 
  unarmed attack rate of attacks per round 
  while grappling.  
  Step 1—Grab: The combatant makes a 
  melee touch attack to grab the target. If the 
  combatant fails to hit the target, the 
  combatant fails to start the grapple.  
  Step 2—Hold: Make an opposed grapple 
  check. If the combatant succeeds, the 
  combatant has started the grapple, and the 
  combatant deals damage to the target as if 
  with an unarmed strike.  
  If the combatant loses, the combatant fails 
  to start the grapple. The combatant 
  automatically loses an attempt to hold if 
  the target is two or more size categories 
  larger than the combatant is (but the 
  combatant can still make an attempt to 
  grab such a target, if that's all the 
  combatant wants to do).  
  Step 3—Move In: To maintain the 
  grapple, the combatant must move into the 
  target's 
  space. 
  Moving, 
  as 
  normal, 
  provokes attacks of opportunity from 
  threatening enemies, but not from the 
  combatant's target.  
  Step 4—Grappling: The combatant and 
  the target are now grappling.  
  If a combatant's target is already grappling 
  someone else, then the combatant can use 
  an attack to start a grapple, as above, 
  except that the target doesn't get an attack 
  of opportunity against the combatant, and 
  the 
  combatant's 
  grab 
  automatically 
  succeeds. The combatant still has to make 
  a successful opposed grapple check to deal 
  damage and must still move in to be part 
  of the grapple.  
  When a combatant is grappling (regardless 
  of who started the grapple), the combatant 
  can make an opposed grapple check as an 
  attack. If the combatant wins, the 
  combatant can do the following:  
  Damage A combatant's Opponent: A 
  combatant deals damage as with an 
  unarmed strike (1d3 points for Medium-
  size attackers or 1d2 points for Small 
  attackers, plus Strength modifiers). If a 
  combatant wants to deal normal damage, 
  the combatant suffers a -4 penalty on the 
  grapple check. Exception: Monks deal 
  more damage on an unarmed strike than 
  other combatants, and the damage is 
  normal. However, they can choose to deal 
  their damage as subdual damage when 
  grappling without paying the usual -4 
  penalty for changing normal damage to 
  subdual damage.  
  Pin: A combatant can hold an opponent 
  immobile for 1 round. (If a combatant gets 
  multiple attacks, the combatant can use 
  subsequent 
  attacks 
  to 
  damage 
  the 
  opponent. A combatant can't use a weapon 
  on a pinned opponent or attempt to 
  damage or pin a second opponent while 
  holding a pin on the first.) While a 
  combatant is pinned, opponents other than 
  the one pinning the combatant get a +4 
  bonus 
  on 
  attack 
  rolls 
  against 
  the 
  combatant (but the combatant is not 
  helpless).  
  Break Another's Pin: A combatant can 
  break the hold that an opponent has over 
  an ally.  
  
  D20 Combat Rules 
   
  Page 10 
  Escape: A combatant can escape the 
  grapple. A combatant can take whatever 
  movement the combatant gets. If more 
  than 
  one 
  opponent 
  is 
  grappling 
  a 
  combatant, the combatant's grapple check 
  result has to beat all their check results to 
  escape. (Opponents don't have to try to 
  hold a combatant if they don't want to.)  
  When 
  an 
  opponent 
  has 
  pinned 
  a 
  combatant, 
  the 
  combatant 
  is 
  held 
  immobile (but not helpless) for 1 round. 
  The combatant can make an opposed 
  grapple check as a melee attack. If the 
  combatant wins, the combatant escapes the 
  pin, but the combatant is still grappling.  
  In addition to making opposed grapple 
  checks, a combatant has a few other 
  options while grappling.  
  Weapons: A combatant can attack with a 
  light weapon while grappling (but not 
  while pinned or pinning). A combatant 
  can't attack with two weapons while 
  grappling.  
  Wriggle Free: A combatant can make an 
  Escape Artist check (opposed by a 
  combatant's opponent's grapple check) to 
  get out of a grapple or out of being pinned 
  (so that the combatant is just being 
  grappled). Doing so counts as a standard 
  action; if a combatant escapes a grapple, 
  the combatant can also move in the same 
  round.  
  Several combatants can be in a single 
  grapple. Up to four combatants can 
  grapple a single opponent in a given 
  round. Opponents that are one size 
  category smaller than a combatant count 
  for half, opponents that are one size 
  category larger than a combatant count 
  double, and opponents two or more size 
  categories larger count quadruple.  
  Additional enemies can aid their friends 
  with the aid another action.  
  While a combatant is grappling, that 
  combatant's ability to attack others and 
  defend a itself is limited.  
  No Threatened Area: A combatant 
  doesn't threaten any area while grappling.  
  No Dexterity Bonus: A combatant loses 
  it's Dexterity bonus to AC (if a it has one) 
  against opponents a it isn't grappling. (A 
  combatant can still use the bonus against 
  opponents the combatant is grappling.)  
  Heal a dying friend 
  [Standard][AoO: Yes] 
  This may involve the use of a spell, 
  administration of a potion, or a use of the 
  Healing skill.  
  Light a torch  
  [Full][AoO: Yes] 
  Self explanatory.  
  Load a hand crossbow 
  [Move Equivalent][AoO: Yes] 
  Self explanatory.  
  Load a heavy crossbow 
  [Full][AoO: Yes]  
  Self explanatory.  
  Load a light crossbow  
  [Move Equivalent][AoO: Yes] 
  Self explanatory.  
  Load a repeating crossbow  
  [Full][AoO: Yes] 
  Self explanatory.  
  Lock or unlock weapon in 
  locked gauntlet  
  [Full][AoO: Yes] 
  
  D20 Combat Rules 
   
  Page 11 
  Self explanatory.  
  Loose a shield  
  [Move Equivalent][AoO: No] 
  Self explanatory.  
  Make Spellcraft check on 
  counterspell attempt  
  [Free][AoO: No] 
  Self explanatory.  
  Mount or dismount  
  [Move Equivalent][AoO: No] 
  Self explanatory.  
  Move a heavy object  
  [Move Equivalent][AoO: Yes] 
  Self explanatory.  
  Open a door  
  [Move Equivalent][AoO: No] 
  Self explanatory.  
  Overrun (charge)  
  [Standard][AoO: Yes] 
  A combatant can try to overrun as part of a 
  charge action against an opponent that is 
  one size category larger, the same size, or 
  one size smaller than the combatant. Only 
  one attempt to overrun can be made per 
  charge.  
  An overrun takes place during the 
  movement portion of a charge. With an 
  overrun, a combatant attempts to move 
  through the opponent's area.  
  First, a combatant must charge at least 10 
  feet in a straight line into the defender's 
  space.  
  Then the defender chooses either to avoid 
  the combatant or to block the combatant. 
  If he avoids the combatant, the combatant 
  keeps moving. (A combatant can always 
  move through the space occupied by 
  someone who lets a combatant by.) If the 
  defender blocks a combatant, make a trip 
  attack against the defender (see Trip, 
  below). If the combatant succeeds in 
  tripping the defender, the combatant can 
  continue the charge in a straight line as 
  normal.  
  If a combatant fails and is tripped in turn, 
  the combatant is prone in the defender's 
  space. If a combatant fails but is not 
  tripped, the combatant has to move 5 feet 
  back the way the combatant came. If that 
  space is occupied, the combatant falls 
  prone in that space.  
  Pick up an item  
  [Move Equivalent][AoO: Yes] 
  A character must be in the same space as 
  the item to be picked up.  
  Prepare spell components to 
  cast a spell  
  [Free][AoO: No] 
  Self explanatory.  
  Prepare to throw oil  
  [Full][AoO: Yes] 
  Self explanatory.  
  Ready  
  [Standard][AoO: No] 
  The ready action lets a combatant prepare 
  to take an action later, after a combatant's 
  turn is over but before a combatant's next 
  one has begun. Readying is a standard 
  action, so a combatant can move as well. It 
  does not provoke an attack of opportunity 
  (though the action that a combatant readies 
  might do so).  
  
  D20 Combat Rules 
   
  Page 12 
  Only partial actions can be readied. See 
  the table in the description of "Start full 
  round action" for a list of standard partial 
  actions.  
  Specify the partial action a combatant will 
  take and the conditions under which it will 
  be taken. When those conditions are met, 
  the combatant may take the readied partial 
  action. The partial action comes before the 
  action that triggers it. For the rest of the 
  fight, the combatant's initiative result is 
  the count on which the combatant took the 
  readied action, and the combatant acts 
  immediately ahead of the combatant 
  whose action triggered the readied action.  
  If the combatant takes the readied action 
  into 
  a 
  subsequent 
  round, 
  and 
  the 
  conditions are met before the combatant's 
  normal initiative, the combatant's initiative 
  rises to that new point in the order of 
  battle, the combatant may take the readied 
  action, and whether that action is taken or 
  not, the combatant does not get a regular 
  action that round.  
  Ready a shield  
  [Move Equivalent][AoO: No] 
  Assumes the shield is being carried or 
  worn, and is not secured in such a way that 
  readying the shield can be done quickly.  
  Ready to interrupt spellcaster  
  [Standard][AoO: No] 
  A combatant can ready an attack against a 
  spellcaster with the trigger "if she starts 
  casting a spell." If a combatant succeeds in 
  damaging the spellcaster or otherwise 
  distracting the spellcaster, the spellcaster 
  may lose the spell the spellcaster was 
  trying to cast (as determined by the 
  Concentration check result).  
   
   
  Readying to Counterspell  
  [Standard][AoO: No] 
  A combatant may ready a counterspell 
  against a spellcaster (often with the trigger 
  "if she starts casting a spell"). In this case, 
  when the spellcaster starts a spell, a 
  combatant get a chance to identify it with 
  a Spellcraft check (DC 15 + spell level). If 
  a combatant does, and if the combatant 
  can cast that same spell (is able to cast it 
  and has it prepared, if a combatant 
  prepares spells), the combatant can cast 
  the 
  spell 
  as 
  a 
  counterspell 
  and 
  automatically ruin the other spellcaster's 
  spell. Counterspelling works even if one 
  spell is divine and the other arcane.  
  A spellcaster can use dispel magic to 
  counterspell another spellcaster, but it 
  doesn't always work.  
  Rebuke undead (use special 
  ability) 
   [Standard][AoO: No] 
  Self explanatory.  
  Refocus (no move) 
  [Full][AoO: No] 
  Refocus is a full-round action during 
  which a combatant cannot move. The 
  combatant moves up in the initiative count 
  and is positioned as though it had rolled a 
  20 on the initiative check. Other modifiers 
  (such as for Dexterity and for the 
  Improved Initiative feat) also apply to this 
  roll of 20 when determining the new 
  initiative check result.  
  Retrieve a stored item  
  [Move Equivalent][AoO: Yes] 
  Self explanatory.  
   
  
  D20 Combat Rules 
   
  Page 13 
  Run  
  [Full][AoO: Yes] 
  The combatant can move up to four times 
  the combatant's base speed in a straight 
  line (or three times base speed if the 
  combatant is in heavy armor). The 
  combatant loses any Dexterity bonus to 
  AC since the combatant can't avoid 
  attacks.  
  A combatant can run for a number of 
  rounds 
  equal 
  to 
  the 
  combatant's 
  Constitution score, but after that, the 
  combatant must succeed at a Constitution 
  check (DC 10) to continue running. The 
  combatant must check again each round in 
  which the combatant continues to run, and 
  the DC of this check increases by 1 for 
  each check a combatant has made. When a 
  combatant fails this check, the combatant 
  must stop running. A combatant who has 
  run to the limit must rest for 1 minute (10 
  rounds) before running again. During a 
  rest period, the combatant can move no 
  faster than a normal move.  
  Sheathe a weapon  
  [Move Equivalent][AoO: Yes] 
  A character with the two-weapon fighting 
  Feat can sheathe two weapons on the same 
  action.  
  Speak  
  [Free][AoO: No] 
  The DM may place limits on what may be 
  reasonably communicated in a six-second 
  combat round.  
  Stand up from prone 
  [Move Equivalent][AoO: No] 
  Self explanatory.  
   
   
  Start full round action  
  [Partial][AoO:No] 
  The start full-round action partial action 
  lets a combatant start undertaking a 
  miscellaneous full-round action, which the 
  combatant can complete on the following 
  round (even with a partial action). This 
  option is normally used when a combatant 
  has been magically slowed or is suffering 
  some other condition that restricts the 
  combatant from taking full round actions.  
  Strike a weapon  
  [Standard][AoO: Yes] 
  A combatant can use a melee attack with a 
  slashing or bludgeoning weapon to strike a 
  weapon or shield that a combatant's 
  opponent 
  is 
  holding. 
  The 
  attacking 
  weapon must be no more than one size 
  category 
  smaller 
  than 
  the 
  weapon 
  attacked. (Treat a buckler as Small, a small 
  shield as Medium-size, a large shield as 
  Large, and a tower shield as Huge.) Doing 
  so provokes an attack of opportunity from 
  the opponent because the combatant is 
  diverting it's attention from the opponent 
  to the opponent's armaments.  
  Then the attacker and the defender make 
  opposed attack rolls. If the attacker wins, 
  the attacker has made a successful attack 
  against the weapon or shield.  
  Strike an object  
  [Standard][Aoo: Maybe] 
  Attacking an inanimate, immobile object 
  not in use by a combatant does not 
  provoke an attack of opportunity. An 
  inanimate, immobile object has an AC of:  
  10 - 5 for no Dexterity + its size modifier.  
  Immobile objects are easy to hit. With a 
  melee weapon, the combatant gets a +4 
  bonus to the attack roll. If a combatant 
  
  D20 Combat Rules 
   
  Page 14 
  takes a full-round action to line up a shot 
  (as with the coup de grace against a 
  helpless foe), the combatant gets an 
  automatic hit with a melee weapon and a 
  +5 attack bonus with a ranged weapon. 
  (Objects, however, are immune to critical 
  hits.)  
  Animated objects count as combatants for 
  AC purposes.  
  Attacking a held, carried, or worn object 
  provokes an attack of opportunity. Objects 
  that are held, carried, or worn by a 
  combatant, are harder to hit. The object 
  uses the combatant's Dexterity modifier 
  (not its own –5) and any magic deflection 
  bonus to AC the combatant may have. The 
  attacker doesn't get any special bonus for 
  attacking the object. If the target object is 
  in the opponent's hand, it gets a +5 AC 
  bonus because the opponent can move it 
  quickly out of harm's way.  
  Table: Size and AC of Objects  
  Size           
  AC Modifier 
  Colossal        
  -8 
  Gigantic        
  -4 
  Huge           
  -2 
  Large           
  -1 
  Medium-size     
  +0 
  Small           
  +1 
  Tiny            
  +2 
  Diminutive      
  +4 
  Fine            
  +8 
  Throw a two-handed weapon 
  with one hand  
  [Full][AoO: Yes] 
  Self explanatory.  
  Trip an opponent 
  [Varies][AoO: No] 
  A combatant can try to trip an opponent as 
  a melee attack. A combatant can only trip 
  an opponent who is one size category 
  larger than a combatant, the same size, or 
  smaller.  
  Making a Trip Attack: Make a melee 
  attack as a melee touch attack. If the attack 
  succeeds, make a Strength check opposed 
  by the defender's Dexterity or Strength 
  check (whichever ability score has the 
  higher modifier). A combatant gets a +4 
  bonus for every size category he is larger 
  than Medium-size or a -4 penalty for every 
  size category he is smaller. The defender 
  gets a +4 stability bonus on his check if he 
  has more than two legs or is otherwise 
  more stable than a normal humanoid. If a 
  combatant win, a combatant trip the 
  defender. If a combatant lose, the defender 
  may immediately react and make a 
  Strength check opposed by a combatant's 
  Dexterity or Strength check to try to trip a 
  combatant.  
  A tripped combatant is prone. Standing up 
  from prone is a move-equivalent action.  
  A combatant may make a trip attack 
  against a mounted opponent. The defender 
  may use his Ride skill in place of his 
  Dexterity 
  or 
  Strength 
  check. 
  If 
  a 
  combatant succeed, a combatant pull the 
  rider from his mount.  
  This attack form substitutes for a melee 
  attack, not an action. As a melee attack, it 
  can be used once in an attack or charge 
  action, one or more times in a full attack 
  action, or even as an attack of opportunity.  
  Total defense  
  [Standard][AoO: No] 
  A combatant doesn't attack or perform any 
  other activity other than moving at base 
  speed, but the combatant gets a +4 dodge 
  bonus to AC for 1 round. The combatant's 
  AC improves at the start of this action, so 
  it helps against any attacks of opportunity 
  provoked while moving.  
  
  D20 Combat Rules 
   
  Page 15 
  Turn 
  undead 
  (use 
  special 
  ability)  
  [Standard][AoO: No] 
  Self explanatory.  
  Use a skill that takes 1 action  
  [Standard][Varies] 
  Self explanatory.  
  Use a skill that takes 1 round  
  [Full][Varies] 
  Self explanatory.  
  Use an extraordinary ability 
  [Free][No] 
  Using an extraordinary ability is usually 
  not an action because most extraordinary 
  abilities automatically happen in a reactive 
  fashion. Those extraordinary abilities that 
  are actions are usually standard actions 
  that cannot be disrupted, do not require 
  concentration, and do not provoke attacks 
  of opportunity.  
  Use extraordinary ability  
  [Standard][AoO: No] 
  Self explanatory.  
  Use feat  
  [Varies][Varies] 
  Self explanatory.  
  Use spell-like ability  
  [Standard][AoO: Yes] 
  Using a spell-like ability works like 
  casting a spell in that it requires 
  concentration and provokes attacks of 
  opportunity. Spell-like abilities can be 
  disrupted. If a combatant's concentration is 
  broken, the attempt to use the ability fails, 
  but the attempt counts as if the combatant 
  had used the ability. The casting time of a 
  spell-like ability is 1 action, making its use 
  a standard action, unless the ability 
  description notes otherwise.  
  A combatant may attempt to use a spell-
  like ability on the defensive, just as with a 
  spell. If the Concentration check (DC 15) 
  fails, the combatant can't use the ability, 
  but the attempt counts as if the combatant 
  had used the ability.  
  Use supernatural ability  
  [Standard][AoO: No] 
  Using a supernatural ability is usually a 
  standard action (unless defined otherwise 
  by the ability description). Its use cannot 
  be 
  disrupted, 
  does 
  not 
  require 
  concentration, and does not provoke 
  attacks of opportunity.  
  Use touch spell on one target  
  [Standard][AoO: No] 
  A combatant may take a move before 
  casting the spell, after touching the target, 
  or between casting the spell and touching 
  the target. A combatant can automatically 
  touch one friend or use the spell on itself, 
  but to touch an opponent, the combatant 
  must succeed at an attack.  
  Use touch spell on up to six 
  friends 
  [Full][AoO: Yes] 
  A combatant can touch one friend as a 
  standard action or up to six friends as a 
  full-round action. 
   
   
   
   
  
  D20 Combat Rules 
   
  Page 16 
  Table: Partial Actions  
   
   
   
   
   
   
   
  Attack of 
  Partial Actions 
   
   
  Move 
   
   
  Opportunity* 
  Attack Partial Actions 
    Attack (melee) 
   
   
  5-ft. step  
   
  No 
    Attack (ranged)  
   
  5-ft. step  
   
  Yes 
    Attack (unarmed)  
   
  5-ft. step  
   
  Maybe 
    Partial charge 
   
   
  Yes (special)** 
   
  No 
   
  Movement-Only Partial Actions 
    Single move 
   
   
  Yes 
   
   
  No 
    Partial run 
   
   
  x2 
   
   
  Yes 
   
  Miscellaneous Partial  
  Actions*** 
   
   
  5-ft. step  
   
  Maybe 
   
  Magic Partial Actions 
  Cast a spell****  
   
  5-ft. step   
   
  Yes 
  Activate magic item  
   
  5-ft. step   
   
  Maybe 
  Use special ability*  
   
  5-ft. step   
   
  Maybe 
  Concentrate to maintain a spell  
  5-ft. step   
   
  No 
  Dismiss a spell  
   
   
  5-ft. step   
   
  No 
   
  Special Partial Action 
    Start full-round action 
   
  No 
   
   
  Maybe 
   
  *Regardless of the action, if a combatant moves within or out of a threatened area, a 
  combatant usually provokes an attack of opportunity. This column indicates whether the 
  action itself (not the moving) provokes an attack of opportunity. 
  **A combatant must move in a straight line before attacking and must move at least 10 
  feet. 
  ***Those actions defined as standard or move-equivalent actions. Most allow a 5-foot 
  step, though actions that are variant charge actions follow the move for partial charge. 
  ****Unless doing so is a full-round action, in which case a combatant could start a full-
  round action and then finish it the next round with a cast a spell action. Spells that take 
  longer than 1 full round to cast take twice as long to cast. 
   
   
   
   
   
  
  D20 Combat Rules 
   
  Page 17 
  COMBAT MODIFIERS 
  Attack Roll Modifiers 
  Use these adjustments whenever a combatant is making a melee, ranged, full, or other 
  type of attack action.  
  Table: Attack Roll Modifiers  
  Circumstance                     
  Melee              Ranged 
  Attacker flanking defender*     
  +2                      
  Attacker on higher ground      
  +1                     +0 
  Attacker prone                  
   
  -4                     ** 
  Attacker invisible              
   
  +2***              +2*** 
  Defender sitting or kneeling    
  +2                    -2 
  Defender prone                   
  +4                    -4 
  Defender stunned, cowering,  
     or off balance                   
  +2***              +2*** 
  Defender climbing  
     (cannot use shield)              
  +2***              +2*** 
  Defender surprised or  
     flat-footed                     
   
  +0***              +0*** 
  Defender running                 
  +0***              -2*** 
  Defender grappling  
     (attacker not)                  
   
  +0***              +0**** 
  Defender pinned                  
  +4***              -4*** 
  Defender has cover              
  —–— See Cover —–— 
  Defender concealed or  
     invisible                      
   
  — See Concealment — 
  Defender helpless                
  See Helpless Defenders  
  *A combatant flanks a defender when a combatant has an ally on the opposite side of the 
  defender threatening him. Rogues can sneak attack defenders that they flank. 
  **Most ranged weapons can't be used while the attacker is prone, but a combatant can 
  use a crossbow while prone. 
  ***The defender loses any Dexterity bonus to AC. 
  ****Roll randomly to see which grappling combatant a combatant strikes. That defender 
  loses any Dexterity bonus to AC. 
   
   
  
  D20 Combat Rules 
   
  Page 18 
  Helpless Combatants:  
  A melee attack against a 
  helpless 
  combatant gets a +4 circumstance bonus 
  on the attack roll. A ranged attack gets no 
  special 
  bonus. 
  A 
  helpless 
  defender 
  (naturally) can't use any Dexterity bonus 
  to AC. In fact, his Dexterity score is 
  treated as if it were 0 and his Dexterity 
  modifier to AC as if it were –5 (and a 
  rogue can sneak attack him).  
  Two Weapon Fighting:  
  If a combatant wields a second weapon in 
  the off hand, that combatant can get one 
  extra attack per round with that weapon. 
  Fighting in this way is very hard, however, 
  and a combatant suffers a -6 penalty for 
  regular attacks with a combatant's primary 
  hand and a -10 penalty to the attack with a 
  combatant's off hand. A combatant can 
  reduce these stiff penalties in three ways:  
  * If a combatant's off-hand weapon is 
  light, the penalties are reduced by 2 each. 
  A light weapon is one that's smaller than a 
  weapon a combatant could use in one 
  hand. Its size category is smaller than a 
  combatant's. (An unarmed strike is always 
  considered light.)  
  * The Ambidexterity feat reduces the off-
  hand penalty by 4.  
  * The Two-Weapon Fighting feat reduces 
  both penalties by 2.  
  Double Weapons:  
  A combatant can use a double weapon to 
  make an extra attack as if the combatant 
  were fighting with two weapons. The 
  penalties apply as if the off-hand weapon 
  were light.  
  Inflicting Damage 
  Damage Rolls 
  If the attack roll result equals or exceeds 
  the target's AC, the attack is successful, 
  and the combatant deals damage. Roll the 
  appropriate damage for a combatant's 
  weapon. Damage is deducted from the 
  target's current hit points.  
  Minimum Weapon Damage 
  If penalties to damage bring the damage 
  result below 1, a hit still deals 1 point of 
  damage.  
  Off-Hand Weapon 
  When a combatant deals damage with a 
  weapon in the combatant's off hand, a 
  combatant add only one-half of the 
  combatant's Strength bonus.  
  Wielding 
  a 
  Weapon 
  Two-
  Handed 
  When a combatant deals damage with a 
  weapon that the combatant is wielding 
  two-handed, the combatant adds one and 
  one half times the combatant's Strength 
  bonus. Light weapons don't get this higher 
  Strength bonus when used two-handed.  
  Unarmed Strike Damage 
  An unarmed strike from a Medium-size 
  combatant deals 1d3 points of damage 
  (with a combatant's Strength modifier, as 
  normal). A Small combatant's unarmed 
  strike deals 1d2 points of damage. All 
  damage is subdual damage. Unarmed 
  strikes count as light weapons (for 
  purposes of two-weapon attack penalties 
  and so on).  
  
  D20 Combat Rules 
   
  Page 19 
  Dealing Normal Damage 
  A combatant can specify that it's unarmed 
  strike will deal normal damage before it 
  makes an attack roll, but the combatant 
  suffers a -4 penalty on it's attack roll 
  because it has to strike a particularly 
  vulnerable spot to deal normal damage.  
  Critical Hits 
  When a combatant makes an attack roll 
  and gets a natural 20, the combatant hits 
  regardless of the target's AC, and the 
  combatant has scored a threat. The hit 
  might be a critical hit (or "crit"). To find 
  out if it's a critical hit, the combatant 
  immediately makes a critical roll — 
  another attack roll with all the same 
  modifiers as the attack roll the combatant 
  just made. If the critical roll also results in 
  a hit against the target's AC, the 
  combatant's original hit is a critical hit. If 
  the critical roll is a miss, then the 
  combatant's hit is just a regular hit.  
  A critical hit means that the attacker rolls 
  for damage more than once, as indicated 
  by the weapon description for the weapon 
  that scored the threat, with all the 
  attacker's usual bonuses, and add the rolls 
  together to get total damage.  
  Exception: Bonus damage represented as 
  extra dice is not multiplied when a 
  combatant score a critical hit.  
  Increased Threat Range 
  Sometimes a combatant's threat range is 
  greater than 20. In such cases, a roll below 
  20 is not an automatic hit. Any attack roll 
  that doesn't result in a hit is not a threat.  
   
  Increased Critical Multiplier 
  Some weapons, deal better than double 
  damage with a critical hit.  
  Multiplying Damage 
  Sometimes a combatant multiplies damage 
  by some factor, such as when a combatant 
  scores a critical hit. Roll the damage (with 
  all modifiers) multiple times and total the 
  results.  
  Cover and Concealment 
  Depending on the situation, a combatant 
  may gain bonuses or suffer penalties on 
  the combatant's attack roll. A combatant's 
  DM judges what bonuses and penalties 
  apply.  
  Cover 
  Cover provides a bonus to a combatant's 
  AC. The more cover a combatant has, the 
  bigger the bonus.  
  Table: Cover  
  Degree of    Cover AC     Cover Reflex 
  Cover          Bonus            Save Bonus 
  1/4 
       +2                  +1 
  1/2 
       +4                  +2 
  3/4 
       +7                  +3 
  9/10 
       +10                +4* 
  Total 
       -                     - 
  *Half damage if save is failed; no damage 
  if successful. 
   
   
  
  D20 Combat Rules 
   
  Page 20 
  Cover and Attacks of 
  Opportunity 
  An attacker can't execute an attack of 
  opportunity against a combatant with one-
  half or better cover.  
  Cover and Reach Weapons 
  If a combatant is using a reach weapon, a 
  combatant standing between the attacker 
  and the target provides cover to the target.  
  Generally, if both of the other combatants 
  are the same size, the one in the back has 
  one-half cover (+4 AC). If a combatant hit 
  the combatant providing cover, it takes no 
  damage because the attacker would strike 
  it with the haft of the weapon.  
  Degree of Cover 
  Cover 
  is 
  assessed 
  in 
  subjective 
  measurements of how much protection it 
  offers a combatant. The DM determines 
  the value of cover. This measure is not a 
  strict mathematical calculation because a 
  combatant gains more value from covering 
  the parts of the body that are more likely 
  to be struck.  
  Cover Reflex Save Bonus 
  Add this bonus to Reflex saves against 
  attacks that affect an area. For nine-tenths 
  cover, a combatant also effectively has 
  improved 
  evasion. 
  These 
  bonuses, 
  however, only apply to attacks that 
  originate or spread out from a point on the 
  other side of the cover.  
   
   
  Striking the Cover Instead of a 
  Missed Target 
  If it ever becomes important to know 
  whether the cover was actually struck by 
  an incoming attack that misses the 
  intended target, the DM should determine 
  if the attack roll would have hit the 
  protected target without the cover. If the 
  attack roll falls within a range low enough 
  to miss the target with cover but high 
  enough to strike the target if there had 
  been no cover, the object used for cover 
  was struck. This can be particularly 
  important to know in cases where a 
  combatant uses another combatant as 
  cover. In such a case, if the cover is struck 
  and the attack roll exceeds the AC of the 
  covering 
  combatant, 
  the 
  covering 
  combatant takes the damage intended for 
  the target.  
  If the covering combatant has a Dexterity 
  bonus to AC or a dodge bonus, and this 
  bonus keeps the covering combatant from 
  being hit, then the original target is hit 
  instead. The covering combatant has 
  dodged out of the way and didn't provide 
  cover after all. A covering combatant can 
  choose not to apply his Dexterity bonus to 
  AC and/or his dodge bonus, if his intent is 
  to try to take the damage in order to keep 
  the covered combatant from being hit.  
  Concealment 
  Concealment includes all circumstances 
  where nothing physically blocks a blow or 
  shot but where something interferes with 
  an attacker's accuracy.  
  Concealment is subjectively measured as 
  to how well concealed the defender is. 
  Concealment always depends on the point 
  of view of the attacker.  
  
  D20 Combat Rules 
   
  Page 21 
  Concealment Miss Chance 
  Concealment gives the subject of a 
  successful attack a 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. 
  When 
  multiple 
  concealment 
  conditions apply to a defender, use the one 
  that would produce the highest miss 
  chance. Do not add the miss chances 
  together.  
   
  Table: Concealment 
  Concealment 
  Example  
   
   
   
  Miss Chance 
  One-Quarter 
  Light fog; moderate darkness; light foliage 
  10% 
  One-Half  
  Dense fog at 5ft.  
   
   
  20% 
  Three-quarters 
  Dense foliage 
   
   
   
  30% 
  Nine-tenths 
  Near total darkness 
   
   
  40% 
  Total 
   
  Attacker blind; target invisible;  
   
  50% 
   
   
  total darkness; dense fog at 10 ft. 
   
   
   
  
SOURCE: textdata/thevault/Dungeons & Dragons [multi]/3rd Edition (3.x)/3rd Party/Frog God Games/Play Aids/d20 - FGG - Combat Rules.pdf