Decrepify and negative IAS


Diabloii.Net Member
Decrepify and negative IAS

Greetings. I finished my military service about a month ago and started playing D2 again now that I have the time to do so. Anyway, 1.13 quickly showed its cheeziness and now I'm sporting around with Grief and a wolfbarb without most of its essence, just the Feral Rage and huge life (though that could really be most of its essence). I'm building a wolfbarb from the scratch but before I proceed any further, I want to take a look at his performance.

Since I've never been much of a theorycrafter, could someone explain to me how the negative IAS from Decrepify works? Is there a way to negate it, i.e. wear more IAS than it's needed to hit the 'normal' breakpoint?
So far I've understood that it would take off 50% of my effective IAS (EIAS) and then determine my speed. There's another problem: I'm not even sure what my attack speed is since guides say +31% IAS Grief PB hits 5 frames but the wereform calculator says 7 when I use the normal attack that I often hear I should use. Someone has the correct answer? It would help doing the math if I ever find out what formula I should use and where to put the decrepify modifier.

The wereform speed calculator shows that no OIAS would boost my Feral Rage's speed ever, nor has it ever boosted it. So, what does Decrepify actually do in wereform attack speed formula?

Wereform Attack Speed Formula
Well, it matches every datapoint of TheDragoon's for the Werebear chart with One-handed Axe of base speed 30, and the Werewolf chart with One-handed Axe of base speed 0. So I think it's pretty safe to say that this is the correct formula. :)

delay = [256*(WeaponBase + 1) / [(weapon ias+wsm+100)*256/100]]

prev frames = 10 or 9 (Bear or Wolf, respectively)

Anim speed = [prev frames * 256 / delay]

Speed increase = [120 * item_ias / (120 + item ias)] + skill ias + wsm
if (Speed increase > 75): Speed increase = 75

WereBase = 11 or 12 (Bear or Wolf, respectively)

Frames = {256*(WereBase + 1)/[(100 + Speed increase)/100*Anim speed]} - 1

Note that skill ias of course includes the Werewolf inherent bonus and is 68 (at slvl20) with TheDragoon's werewolf charts.

As one can see, I renamed some of the variables here, hopefully this way is more clear. In particular, I renamed a1_frames to 'base + 1' as that is what it is normally referred to in the standard weapon speed formula, then gave the different Bases different names to differentiate between weapon base animation length and wereform base animation length. Also 'delay' had been called 'animation speed' earlier in this thread, but I switched it to what it was called originally in the Whirlwind thread.

Although this should work for standard Wereform attacks, I don't know how Fury works. I tried changing just one of 'WereBase', 'prev frames', or 'WeaponBase' to a different value and didn't get an exact match (for the same 1h-axe base 0 chart I used for Werewolf standard attack), although 'prev frames' = 15 was close enough I didn't notice the differences right away.
The usual attack speed formulas

Wereform attack speed formulas

Thread about Decrepify affecting attack speed

I seriously need help.


Diabloii.Net Member
Re: Decrepify and negative IAS

Tupsi said:
I seriously need help.
Yes. Yes you do.

The Wereform calculator is correct, but as you said you should select normal attack as the animation applied for feral rage in that calculator is incorrect IIRC.

My initial bet on decrepify is that it adds -50% skill IAS. You could try the AB.