Blade Fury Analysis by Ceramic Weasel


Guide Author
Dec 24, 2019
Blade Fury Analysis
Originally Posted by Ceramic Weasel, Jul 13, 2009

Blade Fury Analysis

Everything you thought you knew about Blade Fury put to the test, with surprising results


I've been playing Assassins in one form or another for many years, but hadn't paid much attention to the Blade Fury skill until just a few months ago. I was intrigued by the idea of a Furysin. It looked like fun and Blade Fury was said to be a 1pt-wonder skill, making any Fury build highly customizable. I spent several weeks testing equipment combinations, but its performance always left me disappointed. Then, about two weeks after I had given up on the idea, an update to the Arreat Summit on June 15, 2009 included this surprising addition to the skill description:
Arreat Summit said:
The +min/max damage listed on the skill effectively works the same as +min/max damage added to your weapon on normal attacks, except that it is not reduced by the 3/4, 3/8 & 1/4 penalties. So for damage dealing purposes, on blade fury, you could treat it exactly the same as an offweapon source of +min/max damage, ignoring the penalty. This is especially important, as with high levels of blade skills, the +skill damage can deal more than the weapon "half" of the damage.
I almost fell off my chair. This is huge! Do people know about this? It flew in the face of everything I thought I knew about this skill. Nearly all the guides I had read with any mention of Blade Fury had all said the same thing: that this was a 1pt-wonder; additional points in this skill are wasted. But if the above statement is correct, a 20pt investment in Blade Fury could potentially yield THOUSANDS of damage! I immediately dug up my data sheets and started repeating all my tests, this time making no assumptions about what Blade Fury was and wasn't supposed to do. The following is a description of my findings, and the conclusions made therein.

Note: This is not a Furysin guide. This is an analysis of the Blade Fury skill for the purposes of maximizing its damage. The only skills and equipment included are those that affect Blade Fury. I will leave issues of builds and strategies open to discussion.

Abbreviation Key
%ed - % Enhanced Damage
AR - Attack Rating
Avg - Average
BF - Blade Fury
ctc - chance to cast
CB - Crushing Blow
CM - Claw Mastery
CoS - Cloak of Shadows
CS - Critical Strike
Dex - Dexterity
Dmg - Damage
DS - Deadly Strike
ITD - Ignore Target Defense
LCS - Lying Character Screen
Lvl - Level
Mods - Modifiers
PvP - Player vs Player
PvM - Player vs Monster
Str - Strength

Assassin builds that use Blade Fury

Furysin Guide by Ritslev
The Ninja by Frogboybri
The Warrior-Monk (Uber-Trist) by JanusJones

Section A - Skills

Blade Fury

Okay, lets cut right to the chase. The damage from BF isn't very impressive. Or at least, it doesn't appear to be. When you watch the LCS as you place points into BF, your listed damage will only go up by tiny increments. This is because the LCS calculates BF damage with the following formula:

Damage = ((Weapon_Damage + Offweapon_Damage) * (1 + StatsBonus + (+x% Enhanced_Damage) / 100) + Elemental_Damage) * 0.75 + BF_Damage

For those unfamiliar with Diablo 2 damage equations, this means that your normal weapon damage is calculated, modified by items and skills, elemental damage (including magic and poison) is added, the whole thing is hit with a big 3/4 nerf, and then the damage from BF is included, unmodified, at the end.

However, if the recent update to the Arreat Summit is accurate, the real damage formula should look more like this:

Damage = ((Weapon_Damage + Offweapon_Damage) * (1 + StatsBonus + (+x% Enhanced_Damage) / 100) + Elemental_Damage) * 0.75 + BF_Damage * (1 + StatsBonus + (+x% Enhanced_Damage) / 100)

This means that the damage granted by BF would get modified by your Str and/or Dex, as well as all off-weapon sources of enhanced damage. These include skills like CM and auras, as well as items such as Fortitude and Phoenix. This can add up very quickly, but before I did anything else I first had to test the damage equation.

Note on testing: All tests presented in this report were conducted in single player, normal difficulty, on my home network. A character editor was used to create whatever equipment I required and to occasionally reset skill levels. Unless noted otherwise, the test character in all cases was a lvl 90 Assassin with 140 Str and 105 Dex.

Custom rings were used to boost her AR over 70,000, and a small charm with 100% ctc lvl 5 life tap on striking alerted me when a miss occurred. Shuriken were thrown in sets of 2 or more and the average damage of each strike was calculated based on the damage dealt by the entire set.

The target was a lvl 90 Barbarian with no equipment and no skill points allocated. He had exactly 10,000 life and 0% resistances.

For the following tests, I equipped a Fortitude armor and a Last Wish Berserker Axe with maximum (+390%) damage. To ensure accurate results, the ctc effects and CB were removed from the Last Wish. No Venom was used.
Level 1 BF
Listed Damage: 656-1935 (1296 Avg) (216 PvP)
Expected Damage: 707-1999 (1353 Avg) (226 Pvp)

Average damage over 150 hits: 225

Level 20 BF
Listed Damage: 749-2028 (1389 Avg) (232 PvP)
Expected Damage: 1396-2687 (2042 Avg) (340 PvP)

Average damage over 200 hits: 348
Wow, that's pretty clear. Damage from BF is modified by stats, skills and off-weapon %ed at the very least. So what does this mean for our potential damage return?

Take an example Assassin with 150 Str, 100 Dex, maxed CM and the following setup:

Weapon: random claw
Armor: Fortitude
Shield: Phoenix
Other: +skill items granting a total of +15 CM and +15 BF
Mercenary: Act 2 Might (lvl 87) with 'Pride' polearm, Andariel's Visage and Chains of Honor

Note: While the above setup is entirely possible, it's not very practical for reasons discussed later. It is provided here for demonstration purposes only.

The Blade Fury modifiers will then be as follows:

Stats Bonus = 1.87
Lvl 35 Claw Mastery = +171%
Lvl 22 Might (Merc) = +250%
Lvl 20 Concentration = +345%
Fortitude armor = +300%
Phoenix shield = +400%

The difference between 1pt and 20pts in BF, with +15 to the skill, is 152 damage. So now we calculate:

152 * (1+1.87 + (171+250+345+300+400) / 100) ~= 2664

So, by investing 19 additional points into BF, we gain an additional 2,664 damage! Even the godliest Grief-wielding Smiters can't gain that much damage return by maxing Smite, so it seems absurd that a Furysin wouldn't max BF.

Claw Mastery

I knew from my previous testing that Critical Strike from CM applies to BF while wielding a claw. Its kind of hard to miss when you spend hours throwing several thousand shuriken at a defenseless Barbarian. From this observation I had assumed that all of CM's attributes apply to BF, but in the back of my mind I knew I needed to test it. I was determined not to make any more assumptions.

For this test I removed the Fortitude and traded the Last Wish for a claw. CM was boosted to lvl 40 and its affect on each side of the proposed equation was tested separately by using different damage claws and different lvls of BF.
Level 40 CM (+191%ed)

First, the claw side of the equation...

Level 1 BF
Magic Suwayyah (234-312 Dmg)
Expected BF Damage (factoring CS): 1069-1421 (1245 Avg) (208 PvP)

Average damage over 150 hits: 215

...then the BF side of the equation

Level 20 BF
Plain Claws (8-15 Dmg)
Expected BF Damage (factoring CS): 623-666 (645 Avg) (108 PvP)

Average damage over 150 hits: 108
Okay, that all checks out. My current damage equation still holds.

Now for the AR component. For this test I increased my target's defense to 2000, significantly decreased my Furysin's AR and compared the hit rate of a basic claw against that of a hatchet. The AR's listed below are those given by the LCS with normal attack selected.
Level 30 CM (+320%AR)

Claw AR: 14,721
Number of hits over 200 shots: 137 (68.5%)

Hatchet AR: 3,505
Number of hits over 200 shots: 126 (63%)
Hmm, that doesn't look very convincing. The claw hit more frequently, but not as much as I would expect with over 14k AR. I couldn't draw any conclusions from that, so I decided to boost CM to lvl 50 to see what happens.
Level 50 CM (+520%AR)

Claw AR: 21,731
Number of hits over 100 shots: 60

Hatchet AR: 3,505
Number of hits over 100 shots: 61
What the hell? Even with a boost of 7k AR, my hit rate with the claw somehow managed to decrease. That clinches it; the AR component of CM does not apply to Blade Fury while wielding a claw.


With two skills tested and already two unexpected results, I wasn't about to leave this stone unturned. Venom is supposed to be reduced by the 3/4 penalty along with all other elemental damage. In short, it is.

Testing it was tricky, since it's duration is 10 frames (0.4 seconds) and BF hits at a rate of 6 frames, so I had to calculate how much damage the first blade would do before the second hits and reapplies the poison. But because the damage is so regular, the results varied by only 0.8 from the expected damage. I won't bother listing the results in detail, since they're incredibly boring.

Blade Fury counts as a ranged attack, so the bonus from Poison Mastery (Trang-Oul's Claws) is only applied once. Generally speaking, Venom is a weak investment for a Furysin. On successive hits, only 6 frames of poison out of 10 will be applied, and this is then further reduced by the 3/4 penalty such that Venom will typically deal only 45% of it's listed damage (even less for 2H weapons, discussed later).

I also tested elemental and magic damage from other sources (weapon, charms, equipment, etc) and found the same 3/4 penalty applies to these as well. That then brings us to the next section of this report...

Section B - Equipment

Before I start destroying everyone's long-held beliefs about what makes the best Furysin equipment, I'm going to take a moment to review some of the equipment mods that do, and do not, work with Blade Fury. Most of this information can be obtained from Ritslev's guide mentioned above, but I will list it again here for completeness sake.

What works
  • Physical/Weapon Damage (3/4 or 3/8)
  • Elemental Damage (3/4 or 3/8)
  • Deadly Strike
  • Crushing Blow
  • Open Wounds
  • Knockback
  • Prevent Monster Heal
  • Ignore Target Defense
  • Life and Mana Leech
  • Chance to cast on Striking
  • Hit Freezes Target
  • Hit Blinds Target
  • Hit Slows Target
  • Hit Causes Monster to Flee
What doesn't work
  • Faster Cast Rate
  • Increased Attack Speed
  • Chance to cast on Attacking
  • Pierce Target
Most of these are fairly obvious to BF veterans, so I wasn't going to bother testing all of them. However, some of these are highly relevant to damage output, and I felt that they deserved proper testing to remove any ambiguity surrounding them.

The 3/8 Penalty

When wielding 2-Handed weapons, the BF 3/4 penalty increases to 3/8. This is widely known and has been confirmed throughout my testing many times over. What isn't widely known, however, is that the LCS will continue to display damage as though the penalty were 3/4. Do not trust your character screen! 2H weapons are almost always a bad idea for Furysins, since the 3/8 penalty not only applies to your physical weapon damage, but extends to magic and elemental damage too.

To confirm this I compared a Colossus Blade to a Mythical Sword, each with +200%ed and +200 Cold/Fire/Magic. My Assassin had 190 Str and 140 Dex, lvl 1 BF and no other equipment.
Colossus Blade (2H)
Listed damage with normal attack: 1104-1600
Listed damage with Blade Fury: 836-1210 (1023 Avg) (171 PvP)
Expected damage with BF (3/8): 437-629 (533 Avg) (89 PvP)

Average damage over 100 hits: 92
If the elemental component was only suffering a 3/4 penalty, we'd expect to see
126 average PvP damage.

Mythical Sword (1H)
Listed damage with normal attack: 948-1035
Listed damage with Blade Fury: 719-786
Expected damage with BF (3/4): 734-805 (770 Avg) (128 PvP)

Average damage over 100 hits: 131
If that wasn't bad enough, the 3/8 penalty from 2H weapons also extends to Venom. The following test was done with a normal 2H sword, lvl 1 BF, lvl 50 Venom and 140 Str. Blades were thrown in sets of 2, allowing the second to deliver the full dose of poison before the next set was fired.
Level 50 Venom with 2H sword
Average Venom damage per frame: 143.5 (23.9 PvP)

1st Blade (6 frames): 7.3 + 23.9 * 6 * 0.375 = 61
2nd Blade (10 frames): 7.3 + 23.9 * 10 * 0.375 = 97

Expected average damage: (61 + 97)/2 = 79
Observed average damage over 100 hits: 75
In other words, don't use 2H weapons.

Deadly Strike

There's no question that DS works, but I wasn't sure if it worked on the extra damage granted by Blade Fury as well. I'm nothing if not thorough, so yet again I ran some tests. I used a phase blade with +500%ed and 100% DS, lvl 20 BF and put on a Fortitude to boost the BF component slightly higher than the weapon component. If the DS was only applying to the weapon component, the result should be significantly less than my expected damage.
Listed damage with normal attack: 1004-1134
Expected damage with BF (factoring DS): 2596-2813 (2705 Avg) (451 PvP)

Average damage over 100 hits: 460
Awesome. The amazing damage potential of BF just got even better.

Crushing Blow

This stuff is great for PvM, as everyone knows, but when you read the description on the Arreat Summit it says that the damage from CB is halved for "missile weapons". What does this mean for BF when you're wielding a melee weapon and throwing shuriken?

To test this I created a shortbow and club, both with 100% CB, then wailed on my target with normal attack to get a damage benchmark for each. I then repeated the test using lvl 1 BF with both weapons. Alas, no matter what weapon you're wielding, BF always counts as a "missile weapon" for calculating CB damage.

Dual-wielding Claws

Read this post in the Dual-wielding weapon mods that carry over to both attacks? thread for what should be a complete list of secondary weapon modifiers that apply to the attacks of the primary weapon. The following modifiers on the secondary weapon will increase Blade Fury's damage:

  • Skill bonuses
  • Attribute bonuses (Strength and Dexterity)
  • -% Enemy Resistance
+% Skill Damage will be applied once to Holy Shock and Venom and Enchant when cast, but because BF is a ranged attack there'll be no second application.


After all that testing and exposition, you're probably anxious to see some actual weapon comparisons. Many people on these forums have their favourite BF weapons, such as Stormlash, Fleshripper or Last Wish. I tested all of these and lots more, and will post the results of the highest performing weapons, along with others that people may be interested in seeing.

Perform your own equipment comparisons using my Blade Fury Damage Calculator

For these tests my Assassin had lvl 30 CM and lvl 30 BF, was wearing Fortitude, Gore Riders and a Guillaume's helm socketed with a 40%ed jewel. Her Str and Dex altered slightly depending on the weapon used, but in most cases remained at 155 and 105 respectively. This setup provided her with the following, off-weapon damage modifiers:
  • 340% Enhanced Damage
  • 50% Crushing Blow
  • 30% Deadly Strike
  • 10% Open Wounds
  • +151% Enhanced Damage with claws
  • 22% Critical Strike with claws
  • 181-183 Blade Fury base damage
All variable effects on the weapons (specifically damage) were set at maximum, and in the case of runewords a further +15%ed was added for the superior base weapon. To give the non-runewords a fighting chance, they were all socketed with "Lo" runes, granting 20% DS.
The damages listed are the average over 100 hits in PvP

Weapon                     Grade             Damage     Str/Dex
Godly Rare Claw            Ethereal          1226       155/105
Death Ettin Axe            Ethereal          1137       155/105
Lacerator (after Amp)      Ethereal          1137       155/115 (req)
Last Wish Berserker Axe    Ethereal          1132       155/105
Choas Suwayyah             Ethereal          1115       165/105 (weapon)
Stonecrusher               Ethereal          1089       185/105 (weapon/req)
Fury Suwayyah              Ethereal          1088       155/105
Beast Ettin Axe            Ethereal          1050       195/105 (weapon)
Fleshripper                Ethereal          1019       155/105

Bartuc's Cut-Throat        Ethereal, Upped   981        175/125 (weapon)
Last Wish Berserker Axe    Normal            954        155/105
Stormlash                  Ethereal          950        155/105
Choas Suwayyah             Normal            918        165/105 (weapon)
Shadowkiller               Ethereal          898        155/105
Famine Ettin Axe*          Ethereal          848        165/105 (weapon)
BOTD Berserker Axe         Ethereal          810        185/135 (weapon)
Schaefer's Hammer          Normal (must be)  765        190/105 (req)
Faith Colossus Crossbow    Normal (must be)  760        165/105 (req)
Azurewrath                 Normal (must be)  719        165/150 (weapon/req)
Crescent Moon Ettin Axe    Ethereal          712        155/105
Lacerator (before Amp)     Ethereal          644        155/115 (req)
Grief Ettin Axe            Ethereal          557        155/105

*Famine can be made in a Legendary Mallet for extra damage, but I chose not to
because of the Str requirements.
Last Wish: It's worth noting that the first time I conducted weapon tests with lvl 1 BF, Last Wish ranked somewhere below Fury Suwayyah. Thus, a lot of this damage can be contributed to a high lvl BF combined with the lvl 17 Might aura.

Stormlash: I'm sure people are going to reply with various comments about static, CB, greatest PvM weapon ever, etc. Personally I think it's a fantastic weapon... for kickers. It works well in melee because everything swarms you and gets torn up by the static field. But with BF and CoS I'm always firing from a distance, usually using knockback, and lvl 10 static just doesn't have the range to be effective in that situation. For a pure Furysin I would say it's okay, but not great.

Faith: Yeah. Remember what I said about 2H weapons? Well, it goes double for bows since they can't be ethereal.

Famine: What Famine lacks in damage, it makes up in versatility. Nothing will be immune to you, and with an Infinity on your merc, all that elemental damage can become quite respectable. How much it does will vary from creature to creature, depending on their resistances, but even with Conviction it'll never reach the raw power of some of the higher physical damage options.

Grief: Woah, what happened here? The Warrior-Monk guide lists this as one of the best weapons for BF, and looking at the mods I can see how someone might easily think that. But clearly it was never actually tested. I figured that the +X damage mod was not being multiplied properly, so naturally I decided to test it.

For the following test my Assassin had 140 Str, 140 Dex, lvl 1 BF and was wearing Fortitude armor. The base weapon for each test was a phase blade with +200%ed and varying amounts of +X or +X-Y damage.
Phase Blade (+200%ed)      Avg Dmg (60 hits)
+60-120 damage              136
+90 damage                   77
+490 damage                  76
+Nothing                     78
Well that explains it. +X damage doesn't work with BF at all.

So what would be my weapon of choice? At this stage, I'd have to say Fury Suwayyah.

... huh?

Allow me to explain. Last Wish is only effective because of its Might aura, but we can get a higher Might aura from a mercenary. Also, the ctc Life Tap is quite annoying if you rely on CoS at all. Death and Chaos are both great, but they lack ITD which is a real pain. You could get a Blessed Aim merc, and equip him with a Pride, but you'll need some +AR items to make it work. You can equip your merc with an Infinity (I highly recommend this for bosses and champs anyway) and exploit the hell out of that -83% defense, but Conviction's radius isn't enough to cover the whole screen, so you're limited to attacking whatever group of monsters your merc decides to attack.

With Fury I'm not relying on my mercenary all the time (ITD), I don't have to worry about getting a crappy damage roll since Fury's %ed is fixed, and I can make it in a claw with a +3 Blade Fury staffmod. It's also a very appropriately named runeword.


The obvious choice here seems like Phoenix. That +400%ed working on both your weapon and BF damage makes each hit really hurt, but as JanusJones points out in his Warrior-Monk guide, the ctc Firestorm constantly interrupts your stream of shurikens. BF has a rather long windup, and when you're being interrupted every 2-3 hits by a 15 frame casting delay, I had to wonder what the overall affect is on damage over time. So I compared it to some other popular damage dealing shields.

For these tests I opened up my system clock and positioned my Diablo 2 window so that I could watch the seconds ticking by. I used the same setup as with the weapon tests, except I took off the Gore Riders and Guillaume's helm, and boosted my target's life to 20,000. Then I timed (roughly) how long it took to kill my target from the moment I held down the mouse button. The weapon used was an ethereal Fury Suwayyah.
Shield                     Average time (out of 3)
3x 40%ed jewels            7.33 seconds
Dream                      8.67 seconds
Tiamat's + 40%ed jewel     8.67 seconds
Phoenix (+400%ed)          10.67 seconds
To be fair, depending on the distance between you and your target, you should get several shuriken in the air before the first one strikes, and with the right equipment you're likely to kill most PvM targets in 2-3 hits anyway. So, the ctc interruptions from Phoenix may not slow you down as much as the above figures suggest. More field testing is required.

What about Voice of Reason?

Builds based around ctc effects seem to be popular these days, and although Rift's ctc Orb won't work with BF, Voice of Reason's ctc will. I have tried it in PvM and found it to be moderately effective, but my personal opinion is that ctc items which trigger a casting delay are counter-productive for Furysins. I'm sure it's playable with the right equipment, and probably lots of fun, but I'll leave it to others to conduct further research in this area.


I said at the beginning this wasn't a Furysin guide and I'm sticking to that. I don't feel qualified recommending specific equipment options, since I'm still trying them out myself. Damage wise, I tend to look for DS and off-weapon Enhanced Damage before CB, and I consider ITD and Knockback to be high priorities also.

For a final demonstration of a Furysin's true damage potential with a more practical setup, consider the following:

Strength: 160
Dexterity: 90
Armor: Fortitude
Weapon: Ethereal 'Fury' Suwayyah (+3 BF staffmod)
Shield: Monarch socketed with 4x 40%ed jewels
Helm: Guillaume's socketed with 1x 40%ed jewel
Boots: Gore Riders
Gloves: Laying of Hands
Amulet: Highlord's Wrath
Rings: Bul-Kathos x2
Belt: Arachnid's Mesh
Inventory: Torch, Anni, 9x Trap GCs
Switch: CTA / Spirit
Mercenary: Act 2 Might (lvl 87) with 'Infinity' polearm, Andariel's Visage and Chains of Honor

With Battle Orders and CTA prebuffing, this grants +9 CM, +21 BF and +12 Venom

Stats Bonus = 1.87
Weapon Dmg = 219.5 avg
Lvl 41 Blade Fury = 270 avg
Lvl 13 Venom = 275 avg (or 165 on successive hits)
Lvl 29 Claw Mastery = +147%
Lvl 22 Might (Merc) = +250%
Off-weapon item %ed = +500%
Chance of double damage = 22+(1-22/100)*(33+32+15+15) = 96%

Weapon Half = (219.5 * (1 + 1.87 + (147+250+500) / 100) * 1.96 + 165) * 0.75 ~= 3,944
Blade Fury Half = 270 * (1 + 1.87 + (147+250+500) / 100) * 1.96 ~= 6,266

Average Damage per shuriken = 10,210
vs. Demons = 13,191

Not enough? You're right, what was I thinking? Okay, how about this...

Strength: 160
Dexterity: 55
Armor: Fortitude
Weapon: Ethereal perfect 'Death' Ettin Axe
Shield: Monarch socketed with 4x 40%ed jewels
Helm: Guillaume's socketed with 1x 40%ed jewel
Boots: Hsarus' Iron Heel
Gloves: Laying of Hands
Amulet: Highlord's Wrath
Rings: Bul-Kathos / Ravenfrost
Belt: Hsarus' Iron Stay
Inventory: Torch, Anni, 9x Trap GCs
Switch: CTA / Spirit
Mercenary: Act 2 Blessed Aim (lvl 87) with 'Pride' polearm, Andariel's Visage and Chains of Honor

With Battle Orders and CTA prebuffing, this grants +16 BF and +10 Venom
With no ITD she's completely dependent on the Merc, but add some +AR small charms and you should get around 7-8k AR with Blessed Aim

Stats Bonus = 1.6
Weapon Dmg = 370 avg
Lvl 36 Blade Fury = 230 avg
Lvl 30 Venom = 735 avg (or 441 on successive hits)
Lvl 20 Concentration (Merc) = +345%
Off-weapon item %ed = +500%
Chance of double damage = 45+32+15 = 92%

Weapon Half = (370 * (1 + 1.6 + (345+500) / 100) * 1.92 + 441) * 0.75 ~= 6,218
Blade Fury Half = 230 * (1 + 1.6 + (345+500) / 100) * 1.92 ~= 4,880

Average Damage per shuriken = 11,098
vs. Demons = 14,508

Now, that's an impressive Blade Fury.

** Many thanks to everyone who has posted their questions, comments and experiences in this thread! **
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