Ranged Combat Mechanics
 

This article discusses the underlying mechanics at work when ranged attacks are made.

 

Contents

1Possible Outcomes 2Player vs. Environment 2.1White vs. Yellow attacks 2.2Hit Table 2.3Examples

[top]Possible Outcomes

When a ranged attack is made, one of several results will occur. The chance of each of these factors depends on a large number of variables, most of which are described on the Stat Conversion page.

Hit: The attack hits normally.
Critical Hit: The attack hits for double damage.
Miss: The attack doesn't land.
Block: The target blocks some or all of the damage of the attack. Note that blocks only occur when the attack is made in the target's frontal 180 degrees of facing.

The chance of any one of these occurring is determined every time an attack happens. The outcomes are prioritized and when the individual chances are summed to 100%, a single roll is made against that sum. The sum of all the chances is called the Hit Table and is explained below.
Some of the rules above change slightly based on talents, e.g. most Hunters have Mortal Shots, which makes a critical hit do more than double damage.

[top]Player vs. Environment

This section is in regards to attacks made by players against NPCs (DPS). Damage dealt by against NPCs will scale downwards exponentially as the level of the NPC increases above the player, due to decreased chance to hit and crit the NPC. This means that an NPC that is four levels higher than the player is drastically more difficult to hit than an NPC three levels above the player, and this continues as the NPC's level increases. Since Boss mobs are three levels above the player, it is important to understand that even by this point there are already sharp decreases in player damage against such NPCs.
This is more of an issue for melee (due to glancing blows) and casters (due to highly increased resist rates), but ranged attacks are also affected to some degree.

[top]White vs. Yellow attacks

All auto-attack hits are resolved as normal hits and show up as "white" damage in the scrolling combat text. Unlike melee auto-attack, ranged auto-attack (Auto Shot) has a cast (0.5 seconds). This means that it's not possible to use a special at the same time as an Auto Shot would occur without delaying your Auto Shot; you need 0.5 seconds of free time, without any ability being used. To maximize DPS, a shot rotation that takes this into account is needed.
Special attacks show up as "yellow", with only a couple differences:
1. Yellow attacks require mana to be used, white attacks are free.
2. Yellow attacks can not proc certain procs, like Improved Aspect of the Hawk.
In a previous patch, Auto Shot was colored yellow like any other special. This, in combination with the fact that some (most?) specials use a two-roll system, might mean that all Hunter shots use a two-roll system. Currently, all Hunters shots are considered to be using a one-roll system.

[top]Hit Table

The hit table when players attack NPCs is different than the attack table used when NPCs attack players. The hit table is the compilation of all outcomes of a given attack after all modifiers have been applied. The range of the hit table is always 100% -- anything that would be "after" 100% is pushed off the table entirely. The order of priority is:
Miss -> Critical Hit -> Hit [always fills the rest of the table]
It is possible for one or more of these factors to not apply; for example, a sufficient amount of +hit (which is more accurately -miss) can remove the miss portion of the table entirely. A long-standing rumor has it that there's always 1% chance to miss that cannot be prevented. This is incorrect, and stems from caster mechanics (where there is always at least 1% chance for any spell to resist).
Against higher level mobs, players have an increased chance to miss, and a decreased chance to crit.
In terms of PVE, any attack may be blocked by an NPC regardless of whether or not it is a critical hit and thus is it not included on this hit table.

[top]Examples

A Hunter with 25% chance to crit and +5% hit attacks an equal level target. His hit table will be as follows:

Miss: 0% (5% base, - 5% from gear/spec)
Critical Hit: 25% (As displayed by the character sheet)
Hit: 75% (Fills the remainder of the hit table)

The same Hunter now attacks a boss mob. Boss mobs are always considered to be 3 levels higher than you in terms of hit/crit/miss calculations. This is his hit table against such an adversary:

Miss: 4% (5% base, 4% due to 3 levels higher, -5% from gear/spec)
Critical Hit: 24.4% (25% character sheet crit rate, modified downward 0.6% by the NPC's improved Defense Rating)
Hit: 71.6% (Fills the remainder of the hit table)

Comments!

"Unlike melee auto-attack, ranged auto-attack (Auto Shot) has a cast (0.5 seconds). This means that it's not possible to use a special at the same time as an Auto Shot would occur without delaying your Auto Shot; you need 0.5 seconds of free time, without any ability being used."

So, what happens ? Does the auto-shot get replaced, missed ? Or does it restart the auto-shot timer ?

(I'm pretty sure based on observation of my noob hunter that the auto-shot timer restarts and the auto-shot fires after the special finishes, ending up with "pushing" the auto-shot)

"different than" -> "different from"

You list possible outcomes as:
Then you list the hit table as:
I presume that blocks factor in before critical hits ?

I'm feeling absolute shit lately, will rephrase and correct once I'm a bit better.

Also, blocks can occur both on normal hits and crits, so they're not included. Think it's mentioned a bit higher up, but I'll go through all this tonight or something.

Surely if blocks can occur on both crits and normal hits, it's conclusive proof of a two-roll system?

Edit: What do we know about warriors' yellow attacks - one roll or two? Is there *anything* other than basic autoattacks that uses the single-roll table?

What about Arcane Shot then?
Can hit/crit normally.
Can be blocked (hit and crit).
Can be partially resisted (hit and crit).
Can be blocked and partially resisted (hit and crit).
3 rolls? Land/PartiallyBlocked/Miss -- Hit/Crit -- bPartiallyResisted

NPC blocks work differently than player blocks do; notably, they don't take up room on the hit table. Any player attack in the frontal cone can have its value partially or fully blocked. Technically all attacks are two-roll in that sense.

I'd imagine this is fairly easy to test on Attumen -- just blow Recklessness. I'm not really sure how you'd test it for Shamans, but I'd bet 10 bucks that Stormstrike is a two-roll attack.

Under White vs Yellow attacks, maybe make it a bit more clean. Right now it looks a bit wordy. Maybe put a <br></br> between auto attacks part and special attacks.

Or this Forums equivalent of those tags.

This hasn't been updated with the 2-roll system.

miss
 

I ran raids with 142 hit rating, but still I see a miss. Even worse when I'm clearing trash I might see a miss. Any comments or clues why this might happen? I'll try to wws it next.

In my experience, it's usually trash mobs or boss abilities that reduce hit chance.

This is no longer true.
Every attack, spell, ranged, or melee, can be hit capped with enough +hit (check the percentages) so that you will not see *any* "miss"ed attacks. Miss chance is increased against higher leveled mobs, as the article points out.