Agility
- Increases Armor Class by 2 for every point of agility
- Increases the chance of a critical hit with melee and ranged attacks. The amount is dependent on class and level
- Increases the chance to dodge an attack. The amount is dependent on class and level, and is subject to diminishing returns -
see here Defense
- Increases the chance of being missed by an attack:
Each point of defense will increase the chance of being missed by an attack from a same level opponent by .04%, subject to diminishing returns
- Increases the chance to dodge, parry, and block:
Each point of defense will increase the chance you will dodge, parry, or block an attack by .04% for each category, dodge and parry are subject to diminishing returns, but block is not
- Decreases the chance of being affected by a critical hit:
Each point of defense will decrease the chance of being affected by a critical hit by .04%
- Decreases the chance of being affected by a crushing blow:
Each point of defense will decrease the chance of being affected by a Crushing Blow by 2%. The benefit defense will have on a Crushing Blow is limited by your level. In other words, increasing your defense will only reduce the chance of being struck by a crushing blow if your current defense value is below your level maximum unbuffed value.
Attack Power
- Attack power increases your base melee DPS by 1 for every 14 attack power.
- Strength increases your melee attack power by 2 for warriors and paladins
Block Value
- Two points of strength increases your block value by 1
Critical Hits
The way WoW calculates crit rate is over ALL attacks. Crit rate is not based on hits only. In other words, if you have a 5% crit
rate, that 5% chance includes misses. All crit rate adjusting abilities, items, and talents add the flat % to the base % crit
rate. So if I have a 5% base crit rate and then use an item or talent that increases that crit rate (let's use Improved Backstab
talent for example - +30% crit), my new crit with backstab is 35%.
Regarding how defense decreases the rate of critical strikes, each point of defense that a target has over the attacker, the
attacker loses 0.04% chance to crit. So, for example, if a level 60 Rogue is attacking a level 60 Warrior who has 25 defense,
the rogue's crit rate will be decreased by 1%.
To Hit
+ToHit items subtract from your chance to miss. So, ignoring all defensive actions (Block/Parry/Dodge/etc..) if I have 20% crit
chance, 20% miss chance, and 60% hit chance and I equip an item that gives me +5% toHit and +5% crit, my stats become 25% crit,
15% miss chance, 60% hit chance. You can reduce your chance to miss with dual wield below 18% by piling on +toHit items.
New hit chance = (Original hit%) + (toHit modifiers) - (crit modifiers)
60% + 5% - 5% = 60%
New crit chance = (Original crit%) + (crit modifiers)
20% + 5% = 25%
New miss chance - (Original miss%) - (toHit modifiers)
20% - 5% = 15%
Mitigation
Mitigation due to armour is capped at 75%.
Armour cap versus a level 80 mob is 45698
Armour cap versus a level 83 mob is 49905
Rating Conversions
At level 80:
Code:
- 4.91850 defense rating = 1 defense skill
- 16.39450 block rating = 1% block chance
- 39.34799 dodge rating = 1% dodge chance (subject to diminishing returns)
- 49.18499 parry rating = 1% parry chance (subject to diminishing returns)
- 32.78999 hit rating = 1% melee hit chance
- 26.23199 hit rating = 1% spell hit chance
- 32.78999 expertise rating = 1% reduction in opponent's chance to dodge and parry
- 45.90599 critical strike rating = 1% critical strike chance (melee or spell)
- 32.78999 haste rating = 1% haste (melee or spell)
- 81.97498 resilience rating = 1% less chance of being struck by any type of critical strike,
and 2% less damage taken from critical strikes 
Formulas and Relationships
