C/C Attack Speed Basics

When an Assassin equips a second claw, her attack speeds change. I started testing awhile back to try and figure out what governs these changes. Much like my kicking document, I'm typing this up in order to settle in my mind what it is that I've found.

The intention of this is not to provide tables of needed IAS and BoS levels to hit certain speeds, but rather to explain the mechanics of how the WSM and IAS are determined. For tables or calculators to use after you know these numbers I'll refer you to these pages:

WSM

First of all, you should be aware of what a WSM is. WSM stands for Weapon Speed Modifier. This is often referred to as the weapon's base speed. When you see people talking about a -30 claw, they are talking about a claw with a WSM of -30. Lower numbers for WSM mean a faster weapon. A -10 speed weapon is inherently faster than a 10 speed weapon provided they are both the same type of weapon. WSM and IAS (defined below) are not the same thing. A Runic Talon (-30 WSM) of Quickness (40 IAS) does not have a WSM of -70. It is a -30 WSM claw with 40 IAS for attack speed purposes.

Base Attack Speed

Base attack speed is based off of weapon type and character type. Each class has different base attack speeds and maximum attack speeds for the different weapon types. For the assassin class these are:

The base attack speeds in this chart are what an assassins attack speed would be when using these weapons with a 0 WSM, no IAS and Burst of Speed is not active.

The maximum attack speeds in this chart are the upper limit of how fast an assassin can attack with these weapons. After you hit the maximum that is listed here, more IAS will do no good. With the exception of using a multi-hit cross class skill such as Zeal, an assassin can't go any faster than what is listed for the weapon.

Kick skills are listed in this chart on their own. While they utilize the WSM and possibly the IAS off of your weapon, they don't actually attack with that weapon. So, the possible 2 frame follow-up kicks by Dragon Talon don't violate these maximum attack speed values for a given weapon.

You may have heard that Fists of Fire, Claws of Thunder, Blades of Ice and Dragon Claw can attack at 5 frames. They don't. The attack animation includes hits from both claws which has a maximum attack speed of 10 frames. That averages to 5 frames/hit. When people refer to a 5 frame Dragon Claw, they mean 5 frames per hit and a 10 frame overall attack.

IAS

IAS stands for Increased Attack Speed. This modifier increases the rate at which your character attacks. IAS is subject to diminishing returns (see the equation in the EIAS paragraph below). Meaning that as you add more IAS, it has less of an effect on your attack speed. It takes far less IAS to go from a 13-frame attack to a 12-frame attack than it does to go from an 8-frame attack to a 7-frame attack. None of the assassin's standard attacks differentiate between IAS on weapons and IAS on other equipment. When using a Chaos runeword claw, the assassin has access to the Whirl Wind skill which does differentiate between such IAS, but I'll refer you to the barbarian forum for explanations on how the Whirl Wind skill is affected when dual wielding weapons.

EIAS

EIAS stands for Effective Increased Attack Speed. This is found by the following equation:

EIAS = ((120 * IAS) / (120 + IAS)) + skill_ias - WSM

The skill_ias referred to in this equation is the attack speed bonus added by skills such as Burst of Speed and Fanaticism. The bonuses added by these skills are not subject to the diminishing returns. WSM and skill_ias directly affect your EIAS. IAS on your gear does not. Throughout this document I'll be referring to both EIAS and IAS. Make sure you understand the difference, as the two are definitely not interchangeable.

Frames per Attack

Diablo 2 runs at 25 frames per second. Your attack speed is the number of those frames that it takes to complete an attack. I've underlined the word "complete" because "attack" means the full animation, not just the hit. If you watch the attack you'll see your assassin swing the claw out, then hit, and finally the claw swings back to her side. The attack animation isn't done until the claw returns to it's starting position. If you are timing attacks and trying to work out how fast they are, take this into account. If you started timing at the beginning of the attack, you need to stop the timer at the end of the animation, not at the point of the hit.

Because attack animations can't be in fractions of frames, when adding IAS or changing to a weapon with a faster WSM to increase attack speed we have what are called break points. These are the points at which a given setup will add or drop frames to its attack animation length. The various Attack speed tables you might have seen are a listing of where these break points are given certain setups.

Dual Claw Setups

Now that the basics are out of the way, let's move onto some dual claw specific information.

The first thing you probably need to know is which of your claws is dominant. Why? Well, later I'm going to start talking about averaging WSMs and IAS on the non-dominant claw not affecting attack speeds. First of all, when I refer to left hand claw and right hand claw in this document, I mean the claws on the left and right of the Character screen, not the claws in your assassin's left and right hands as you see them while questing or playing. The rules are pretty simple, but still cause confusion at times.

It's normally easier to just equip the claw you wish to be dominant first and on the left-hand side if you are going to use your weapon switch often. A lot of times it will be inconvenient to open your inventory, unequip and then re-equip your left claw. Say, for instance, if you were are in the middle of a fight.

There is a reason to equip a claw first and on the right, but I'll get to than later.

I should mention that in the beta for the 1.10 patch this claw dominance was also affected by using a waypoint, taking a town portal and teleporting, but as of the final version of this patch none of these things affect which of your claws is dominant.

Second, you should know some things about the attacks themselves. I'll divide the Martial Arts attacks up into six types. First we have the normal (default) attack. Second, the "animal" charge-ups Tiger Strike, Cobra Strike, and Phoenix Strike. Third come the "elemental" charge-ups, Fists of Fire, Claws of Thunder, and Blades of Ice. Fourth is the Dragon Claw finisher. In fifth, we have the kick finisher, Dragon Talon. Finally, there is the kick finisher Dragon Tail. Hereafter, I'll simply be referring to normal, animal, elemental, DC (Dragon Claw), Talon, and Tail attacks. Refer back to this if you are unsure which group the attack you are dealing fits into. Dragon Flight isn't included in this list as it doesn't rely solely on attack speed, but rather needs faster cast rate items also. As such, it's out of the scope of this document.

Dual Claw WSM penalty.

When using two claws, the normal, elemental, and DC attacks suffer a penalty of 25 to your WSM. If you have a WSM of -30, it becomes -5 for figuring speeds with these attacks. A WSM of 10 becomes 35 for figuring speeds with these attacks.

Also, for the single claw users out there, the elemental charge-ups can be used with a single claw and still take the WSM penalty although their base attack will be 13 frames with a maximum of 7 frames as opposed to 17 and 10 with dual claws. Normal attacks done with a single claw setup don't take the penalty. DC can't be used with a single claw.

Normal Attack

The only one of the five attack types listed whose attack speed won't be affected by which claw is dominant is the normal attack. So, I'll talk about it separately. The Normal attack alternates between your claws. Each claw uses it's own WSM to determine its attack speed.

Each claw individually will take the WSM penalty of 25 to its WSM.

IAS, however, is additive from both claws. If you have one claw with 40 IAS on it and a second claw with no IAS, the attacks of both claws will be figured with 40 IAS. A setup where one claw has 40 IAS and the other has 20 IAS would lead to figuring the speed of both claws with 60 IAS. This is the only attack where IAS from both claws adds together.

Although this attack takes the WSM penalty of 25 when used with dual claws, it still has a base attack speed of 13 frames and a maximum attack speed of 7 frames.

Animal Charge-ups

These attacks will have a base attack speed of 13 frames and a maximum attack speed of 7 frames when used with two claws.

The animal charge-ups do not take the WSM penalty of 25.

Only the IAS on your dominant weapon will affect your attack speed. IAS on the off-hand claw will not affect attack speed.

These attacks have a base attack speed of 17 frames and a maximum attack speed of 10 frames when used with two claws.

These attacks do take the WSM penalty of 25.

Only the IAS on your dominant weapon will affect your attack speed. IAS on the off-hand claw will not affect attack speed

This attack has a base speed of 17 frames and a maximum speed of 10 frames. It can only be used with dual claws.

This attack does take the WSM penalty of 25.

Only the IAS on your dominant weapon will affect your attack speed. IAS on the off-hand claw will not affect attack speed

Dragon Talon

This attack has a base attack speed of 12 frames and a maximum attack speed of 7 frames with all weapon setups. Dragon Talon also includes multiple subsequent kicks, which have a base attack speed of 4 frames and a maximum attack speed of 2 frames.

This attack does not take the WSM penalty of 25.

Only the IAS on your dominant weapon will affect your attack speed. IAS on the off-hand claw will not affect attack speed

Dragon Tail

Dragon Tail is separated from Dragon Talon for a very good reason. It comes with a WSM penalty all its own. It's a steep penalty of 40 tacked directly onto your WSM. This was not reported in the kicking document (That document will have been changed by the time you read this!).

The attack has a base speed of 12 frames and a maximum speed of 7 frames.

This attack does not take the WSM penalty of 25. Thank God! A total penalty of 65 would be too much to overcome for all but a few builds.

Only the IAS on your dominant weapon will affect your attack speed. IAS on the off-hand claw will not affect attack speed

The only thing left really is to talk about how WSMs are figured for dual claw setups when using attacks other than normal attack. These will differ depending on which side your dominant claw is.

Left side dominant

The left side will be dominant if you've equipped the left one first or if you've weapon switched without resetting claw dominance.

Your WSM for attacks with the left side dominant will be the average of the WSMs of your two claws. A -30 claw used with a -10 claw will yield a WSM of -20. You'll use the -20 WSM to figure your attack speed with all attacks except the normal attack.

Right side dominant

If you're with me up 'till now, you're caught up to where I'm at with all of this. I haven't been able to come up with the equations to figure WSM when the right claw is dominant. Instead, I'm going to have to just give you the current results of my testing on this.

First of all, the WSMs are not averaged normally. Using two claws with the same WSM doesn't seem to cause any problems, but when they have different WSMs, things get strange. Here's what I've posted on this issue so far:

I equipped a greater talon on the right side. By itself, I saw the expected attack speed, 10 fpa. I then equipped a war fist on the left side. The attack speed went to 9 fpa. That's right, equipping a massively slower claw actually increased the attack speed. As a matter of fact, equipping the greater talon on the right followed by the war fist and then adding 25 IAS brought about a 7 frame attack with TS, CS, and PS as well as a 7/2 Dtalon. The speed with FoF, CoT, BoI, and DC was 11 frames (11 frames total for the attack, not 11 frames/claw). Definitely not averaging the WSMs! For this setup, I can determine the effective WSM is -55! Of course, once you weapon switch it changes and the war fist becomes primary with WSMs once again averaged.

The opposite happens if you equip the war fist first and on the right. Then the effective WSM once the greater talon is added becomes 27. That's right, this setup has a base attack with PS of 19 frames, far slower than the war fist alone.

So, although I'm still trying to work out the equations, I can state these things when equipping your right claw first:

1. Equipping a faster claw followed by a slower claw will result in an attack that's quicker than the faster claw by itself

2. Equipping a slower claw followed by a faster claw will result in an attack that's slower than the slower claw by itself

3. Switching weapons will revert the setup back to the default of left claw primary and WSMs averaged. To regain the right claw as primary you need to open the inventory, remove the left claw and then replace it. Your right claw will once again be primary.

4. The greater the difference between the base speeds of the claws, the greater the increase or decrease you'll get.

An Example

Let's just run through this real quick. The setup is as follows:

A shaeled (20 IAS) greater talon (-30 WSM) equipped left as dominant claw.

A dual shaeled (40 IAS) scissors suwayyah (0 WSM) equipped right.

For the purposes of this example we will assume that for some reason she is not wearing any other equipment and running Fade rather than BoS. I'll figure EIAS and use the weapon speed calc at diabloii.net for come up with the frames per attack.

For a normal attack:

WSMs of the claws are taken individually and each claw takes the WSM penalty of 25. So my WSMs are -5 for the greater talon and 25 for the scissors suwayyah. Base attack speed will be 13 frames per attack. I have a total of 60% IAS which counts towards the speed of both claws. My EIAS with each claw is:

EIAS = ((120*IAS)/(120+IAS))+skill_ias-WSM

Greater Talon EIAS = ((120*60) / (120+60)) + 0 - (-5)

Greater Talon EIAS = (7200/180) - (-5)

Greater Talon EIAS = 40-(-5)

Greater Talon EIAS = 45, which equates to a 9 frame attack speed

Scissors suwayyah EIAS = ((120*60)/(120+60)) +0 - 25

Scissors suwayyah EIAS = (7200/180) - 25

Scissors suwayyah EIAS = 40 - 25

Scissors suwayyah EIAS = 15, which equates to a 12 frame attack speed

Base attack speed is 13 frames. WSM is -15, the average of -30 and 0. Only the IAS on my dominant claw counts here, so IAS is the 20% on the greater talon. Once again, no skill_ias. The equation looks like this:

Animal EIAS = ((120*20)/(120+20)) + 0 - (-15)

Animal EIAS = (2400/140) - (-15)

Animal EIAS = 17 - (-15), decimals are dropped when dividing

Animal EIAS = 32, which equates to a 10 frame attack

For an elemental charge-up or DC attack:

Base attack speed is 17. WSM is 10, that's the average of the two claws and then applying the WSM penalty of 25. IAS is once again 20%. The equation looks like this:

Elemental EIAS = ((120*20)/(120+20)) + 0 - 10

Elemental EIAS = 17 - 10

Elemental EIAS = 7, which equates to a 16 frame attack or an average of 8 frames/hit.

For a Dragon Talon attack:

Base attack speed is 12 frames. WSM is -15, the average without the penalty. IAS is 20% again. The equation looks like this:

Dtalon EIAS = ((120*20)/(120+20)) + 0 - (-15)

Dtalon EIAS = (2400/140) - (-15)

Dtalon EIAS = 17 - (-15), decimals are dropped when dividing

Dtalon EIAS = 32, which equates to a 9 frame attack. We would have 3 frame follow-up kicks (from the above section on kicks, 25 to 66 EIAS makes for 3-frame follow up kicks).

For a Dragon Tail attack:

Base attack speed is 12 frames. WSM is 25, that's the average of the two claws plus the penalty of 40 for using Dragon Tail. IAS is 20% again. The equation looks like this:

Dtail EIAS = ((120*20)/(120+20)) + 0 - 25

Dtail EIAS = 17- 25

Dtail EIAS = -8, which equates to a 14 frame attack. What? Negative EIAS you say? Yes, it's possible. It means that your attack will be slower than the base attack speed. The calculator at diabloii.net has -8 EIAS listed as a 13-frame attack for a 25 WSM weapon, but my actual speed testing and the calculator on my site both give the speed as 14 frames.

That's probably why c/c attack speeds can be so confusing. With the setup listed above, I have attack rates of 9, 12, 10, 16(8), 9/3, and 14 frames. Trying to work this out can be overwhelming if you've been playing for a while let alone if you're just starting.

For those interested, here are the attack rates if we equipped the greater talon first and on the right:

Normal attack, 9 and 12 frames (the same)

Animal attacks, 8 frames

Elemental and DC, 13 frames

Talon, 8 frames (only tested a single kick talon)

Tail, 10 frames

I hope I've managed to do what I set out to do here. Give myself and anyone who reads this a clearer understanding of how their attack speeds are affected by dual claw setups. I can't think of anything else to add at the moment, so I must be done.

jrichard