Attack table In August 2005 , a Blizzard representative made the following statement : Based on the implications of this statement , it has been suggested by some players that the result of every melee or ranged attack is decided based on a single server - generated random number ( a single " die roll " made internally on the server ) , checked against a server - side internal table for the attack . Auto attack table . Example 1 . Suppose a mob of equal level is attacking your warrior character in melee . Your Defense skill is maxed out for your level , but has no other bonuses . In the general tab of your spell book , you see that your listed Dodge chance is 4 . 5 % , your listed Parry chance is 6 . 2 % , and your listed Block chance ( you have your shield equipped ) is 5 . 1 % . For the mob attacking you , its attack table will look like this . Now say that you elect to activate this warrior ' s Shield Block skill . Shield Block increases the warrior ' s Block chance by an additional 100 % . For the next attack against your warrior , the mob ' s attack table now looks like this . Note that both the chance of an ordinary hit , and the chance of a Critical hit , has been removed from the possible attack results entirely . Example 2 . Elliot the Rogue is level 80 , and is attacking a boss mob along with the rest of his raid group . He has stocked up on all sorts of + Crit Rating gear , so his crit chance against the boss mob is a whopping 30 % . However , he didn ' t bring any + Hit Rating or + Expertise Rating gear with him , nor does he have the Precision talent ; so the base chance for his attacks against a boss to Miss is 8 % , the base chance for the same attacks to be Parried is 14 % , and the base chance for the same attacks to be Dodged and be Blocked are 6 . 5 % each . Since he is dual - wielding , he incurs an additional + 19 % miss chance on every autoattack swing ; his total miss chance against a boss mob is 27 % . Furthermore , he has a fixed 24 % chance of glancing blows against bosses . When he attacks the boss mob from the front with a white - damage auto - attack , Elliot ' s attack table looks like this . Note that despite his nominal " crit chance " of 30 % , his miss chance from dual - wielding and his glancing blow chance due to the boss ' s high level mean that only 22 % of his attacks are going to be critical hits . This conundrum is sometimes referred to as the Crit Cap — his chance to crit is capped at 22 % , so 2 % of his + crit bonus is wasted . Realizing his mistake , Elliot maneuvers around behind the boss mob to continue his attacks . From behind , a mob cannot parry or block , so Elliot ' s attack table now looks like this . Now that he ' s behind the boss mob , Elliot decides to Backstab it . A Backstab is a special ability ; like other special abilities , the damage dealt by Backstab is displayed in yellow numbers . Special abilities , or yellow - damage attacks , do not incur the + 19 % miss penalty for dual - wielding , nor can they be Glancing Blows . Since Backstab is a yellow - damage attack , it doesn ' t use the standard Attack Table ( c . f . below ) ; however , if it did , Elliot ' s attack table would look like this . Example 3 . Oh no ! Elliot the Rogue has backstabbed the boss mob too hard , and has drawn aggro . The boss whirls around and raises his enormous fist in the air , threatening to pound poor little leather - clad Elliot into paste . Elliot ' s Agility does give him a decent dodge chance , but he doesn ' t have the Lightning Reflexes talent , nor does he have any gear that gives him Dodge Rating or Parry Rating . On the whole , things look grim . The boss mob ' s attack table against Elliot looks like this . Thinking quickly , Elliot activates his Evasion skill . This gives a whopping + 50 % increase to his Dodge chance . The mob ' s attack table now looks like this . Example 4 . Holybrick , the level 80 Protection - specced paladin , has heard rumors that it ' s possible to become " Block Capped " , so that he won ' t take unmitigated ordinary hits when fighting Raid Boss monsters . To this end , he strenuously accumulates piece after piece of gear that bestows bonuses to his Dodge Rating , his Parry rating , and even a rare piece that increases his Block Rating . After much effort , he hovers over the Defenses section of his character sheet , and vs . level 83 and " skull " attackers sees the following : Dodge chance 9 . 6 % , Parry chance 13 . 9 % , Block chance 22 . 2 % . He has also wisely invested 3 talent points in the Sanctuary talent , which reduces his chance to be crit by 6 % - - since raid bosses have a nominal 5 . 6 % crit chance vs . level 80 players , this effectively eliminates any danger of being crit during a boss fight . Eager to try out his toughness , Holybrick boldly marches into a Raid instance with his comrades and pulls a Boss monster . The Boss ' s attack table against Holybrick looks as show to the left . Clearly , Holybrick ' s gearing strategy has left him woefully vulnerable to unblocked hits . What is missing from this equation is his use of Holy Shield . The Holy Shield talent allows him to increase his block chance by 15 % whenever he expends Holy Power . He quickly attacks the boss with Hammer of the Righteous to give himself 1 holy power , then spends it with Shield of the Righteous , thus triggering his Holy Shield . With Holybrick ' s Holy Shield up , the Boss ' s attack table now looks like this : ( to the left ) Holybrick won ' t take unblocked hits as often , but sadly , he ' s still going to take them quite a lot of the time , even when he triggers Holy Shield . He is not " Block Capped " yet . Grimly determined , he saunters out to acquire even better gear . Later , after more wearisome effort , he has found a good deal of tank gear , and has reforged much of it so that it provides Mastery Rating . For a protection paladin , Mastery Rating increases his chance to block , and does so at a rate much higher than an equal amount of Dodge Rating or Parry Rating would increase his chance to dodge or parry . On his character sheet , his Block chance against level 83 or " skull " attackers is shown as a whopping 50 . 5 % . Now , Holybrick is ready . He steps back into the same Raid instance , pulls the same boss monster , and triggers his Holy Shield . Now , the Boss ' s attack table against him looks like this : ( left ) Now , not only is he " Block Capped " , but some of his block chance has actually gotten pushed off the end of the table . His nominal Block chance against this monster , with Holy Shield , should be 65 . 5 % , but there is only " room " on the table for 64 . 5 % of it . If he were to reduce his Mastery Rating a little bit so as to lose 1 % of his Block chance , the Boss ' s attack table wouldn ' t change at all . Melee special attacks by players . Melee special attacks , also called " Yellow - damage " melee attacks due to the color of their on - screen damage numbers , are not resolved the same way as white - damage melee attacks . Yellow damage attacks include all instant attacks ( such as Overpower and Backstab ) and all on - next - swing special attacks ( such as Heroic Strike and Cleave ) . The exact mechanism by which special attacks are resolved is not yet known . What is known , however , is that a special attack made against a mob or a shield - carrying player can be blocked and be a crit at the same time . This result is impossible under the mutually - exclusive attack results table described in the preceding section . Two - roll theory for melee special attacks . In a thread on ElitistJerks , a user named Vulajin kept track of his critical hit rate over many many Backstab s . He corrected for all possible factors he could think of , and in the end discovered that the rate he got was consistent with his attack being resolved using two die rolls : A first roll to determine whether the attack missed ( using the assumed miss chance for the mob targets he was attacking ) , and a second roll to determine whether an attack that didn ' t miss was a critical hit ( using his tooltip Crit chance adjusted for the mob target ' s level ) . If his data are accurate , and if the game mechanics for yellow - damage attacks haven ' t changed since the time that discussion thread was written , then there are at least two random numbers generated to determine the outcome of special attacks . It is unfortunate , though , that these tests were done with Backstab and not with a special attack that can be made against a mob from the front , e . g . Sinister Strike or Heroic Strike . Such data would be more useful , because attacks from the front can be parried and blocked . " All " melee attacks from behind . A player attacking a mob from behind can remove only parry and block from the table since direction doesn ' t affect dodge . Also note that there is a 0 . 5 yard penalty in which direction doesn ' t count . A mob ( or enemy player ) attacking a player from behind will remove parry , block , and dodge from its attack table . Ranged attacks . A ranged attack cannot result in a dodge , parry , or glancing blow . ( On their test realms at one point , Blizzard experimented with allowing a small dodge chance against ranged attacks , but this was considered too harmful to Hunters and the experiment was abandoned . ) This means that ranged attacks can only miss , crit , be blocked , hit normally , or result in a crushing blow ( crushing blows are limited to mobs ) . A post made by Lactose on ElitistJerks shows strong evidence that Hunters do not use a single roll system for their ranged attacks . Banshee ' s Curse , a debuff given by Banshee ( Hyjal ) reduced his chance to hit by 66 % , giving him a Miss chance of 67 . 96 % against a level 70 target . Since his tooltip Crit chance was 35 . 83 % , in a one - roll system the only successful auto - shoot attacks should be crits ; however , both Auto Shots and Multi - Shot successfully hit repeatedly without critting . This means that Hunters use at least a two - roll system for all of their ranged attacks . Attack spells . Spells do not use the above tables . The result of casting a spell against a target are determined in an entirely different manner . See spell hit rating . Magic - damage melee auto - attacks . The attacks of some monsters that do magic damage are actually treated as melee attacks , and use the standard melee auto - attack rules . For example , the melee attacks done by a fire elemental inflict fire damage , but they ' re resolved as an ordinary white - damage auto - attack — they can miss , be dodged , be parried , be blocked ( as of Patch 3 . 0 ) , and do double damage on a crit . The only difference between how a magic - damage melee auto - attack , and an ordinary physical damage melee auto - attack , is resolved is that if the target has any to that school of magic , the same check is made to see if the damage is partially resisted as would happen from a spell . Magic - damage melee special attacks . Some monsters also have melee " specials " ( the equivalent of yellow - damage attacks done by players ) that do magic damage . For example , the Crystal Strike ability of the Erratic Sentries on the Isle of Quel ' Danas inflicts Arcane damage , but is resolved as an ordinary melee special attack — it can miss , be dodged , be parried , and be blocked , and does double damage on a crit . The only difference between how a magic - damage melee special attack , and an ordinary physical damage melee special attack , is resolved is that if the target has any to that school of magic , the same check is made to see if the damage is partially resisted as would happen from a spell . A few player abilities , such as a paladin ' s Seal of Command , are likewise resolved as yellow - damage melee attacks that deal non - physical damage . The odds of the various attack results occurring with one of these attacks are determined the same as for physical melee attacks — the base chances are determined by the player ' s Weapon Skill with the wielded weapon , the miss chance is reduced by the player ' s Hit Rating , the chance to be dodged and parried is reduced by the player ' s Expertise , and the chance to crit is increased by the player ' s Agility and Crit Rating . Magic - damage ranged special attacks . The Arcane Shot of a Hunter , and the Hammer of Wrath and Avenger ' s Shield talent of a Protection - specced Paladin , are resolved as ranged attacks that do non - physical damage . They can miss — rather than be " fully resisted " — and they do double damage on a crit . The only difference is that if a mob target is higher level than the player attacker , or if the target has any resistance to the school of magic used by the attack , the same check is made to see if the damage is partially resisted as would happen from a spell . The odds of the various attack results occurring with one of these attacks are determined the same as for physical ranged attacks — the base chances are determined by the player ' s Weapon Skill with the wielded ranged weapon ( in the case of Hunter abilities ) , the miss chance is reduced by the player ' s Hit Rating , and the chance to crit is increased by the player ' s Agility and Crit Rating .