Fortify

This Fortify guide will lay out what the mechanic is, what it is not and how it can be used in Diablo 4. Although any class can technically access the Fortify mechanic it is the Barbarian, Druid and Necromancer who can take full advantage of it.

What is Fortify

Fortify is a damage reduction mechanic that can reduce incoming damage by at least 15% for a variable period of time. It is not a shield like Barrier and does not work in the same way nor is it affected by any buff that kicks in "While you have an active barrier". You can be Fortified and have a Barrier at the same time.

Fortify itself does nothing for you, it is only when your Fortify level is greater than or equal to your current Life (not Max Life) that you become Fortified and that is when the damage mitigation kicks in.


Attacks building up Fortify	Fortify level equal or higher than health level so you're Fortified!
Fortified and Vulnerable (cracks)	Fortified and Barrier (blue hue) active at the same time

Your health globe will indicate when you have become fortified with a heavy metal encasement around it (image top). If your health level then increases above your Fortify level (you drink a potion or generate health another way) you will become unfortified. This means you can end up flipping between the two states of Fortified and Unfortified very easily so it's a mechanic you should go all in on and stack up on as many Fortify-generating items as you can to ensure you can stay Fortified for the longest period possible.

How Does Fortify Reduce Damage?

Its base damage reduction is 15% but this can be increased by choosing skills and items as detailed below. Once Fortified, you will benefit from at least the base 15% reduction for as long as the level remains above your health level.

If you take a hit that takes your Fortify level below your health you will be Fortified for a portion of the damage below your health line. For example:

You have 700 Health Level
You have 500 Fortify Level
You are hit for 300 reducing your health to 400
The first 100 of that hit you are not fortified
The last 200 of that hit you are fortified.

If you stop attacking and therefore generating Fortify the Fortify level will begin to drop and if it drops below your health line you become Unfortified again.

Fortify is also part of the Overpower calculation.

Fortify Skills

The following active and passive skills generate Fortify or apply bonuses whilst you are Fortified.


Barbarian
Basic Tree
Enhanced Bash Clobbering an enemy grants you 20% Maximum Life (1) as Fortify . Skill
Defensive Tree
Strategic Iron Skin Iron Skin also grants 20% Maximum Life as Fortify. Double this amount if cast while below 50% Life. Skill
Strategic Rallying Cry Rallying Cry grants you 10% Maximum Life as Fortify. While Rallying Cry is active, you gain an additional 2% Maximum Life as Fortify each time you take or deal Direct Damage. Skill
Brawling Tree
Mighty War Cry War Cry grants 15% Maximum Life as Fortify. Skill
Thick Skin Each time you take direct damage gain 0.6% Maximum Life (1) as Fortify. Passive
Counteroffensive While you have Fortify for over 50% of your Maximum Life, you deal 4%[x] increased damage. Damage: Physical Damage Passive
Defensive Stance Increase the Damage Reduction gained while you are Fortified by an additional 2%. Passive
Druid
Basic Tree
Fierce Earth Spike Fortify for 12% of your Maximum Life whenever Earth Spike damages enemies who are Stunned, Immobilized, or Knocked Back. Skill
Enhanced Maul If an enemy is hit by Maul, then Fortify for 8% of your Maximum Life. Skill
Defensive Tree
Preserving Earthen Bulwark Casting Earthen Bulwark grants 18% of your Maximum Life (1) as Fortify . Skill
Enhanced Debilitating Roar Debilitating Roar also Fortifies you for 22% of your Maximum Life (1) . Skill
Companion Tree
Ferocious Wolf Pack Lucky Hit: Your Wolves' attacks have up to a 40% chance to Fortify you for 8% of your Maximum Life (1) . Skill
Wrath Tree
Natural Boulder While you have any Fortify, Boulder has +20% increased Critical Strike Chance. Skill
Natural Trample Casting Trample grants 20% of your Maximum Life (1) as Fortify . Skill
Safeguard Critical Strikes with Earth Skills Fortify you for 3% of your Maximum Life (1). Damage: Physical Damage Tags: Earth, Nature Magic Prerequisite: Can also reach Safeguard via Boulder. Passive
Stone Guard While you have Fortify for over 50% of your Maximum Life, your Earth Skills deal 4%[x] increased damage. Damage: Physical Damage Tags: Earth, Nature Magic Prerequisite: Can also reach Stone Guard via Boulder. Passive
Ultimate Tree
Supreme Grizzly Rage Gain 8% Maximum Life as Fortify per second while Grizzly Rage is active. Skill
Defensive Posture Increases the amount of Fortify you gain from all sources by 5%[+] and you gain 3% Damage Reduction while Fortified. Damage: Physical Damage Passive
Thick Hide Whenever you are Stunned (CC), Immobilized (CC) or Knocked Down (CC), Fortify for 10% of your Maximum Life (1). Damage: Physical Damage Passive
Nature's Resolve 5% chance when struck to Fortify you for 4.4% of your Maximum Life (1). Damage: Physical Damage Passive
Unrestrained Reduce the duration of Control Impairing Effects by 5%. Double this effect while you have Fortify for over 50% of your Maximum Life. Damage: Physical Damage Passive
Natural Fortitude Shapeshifting Fortifies you for 2% of your Maximum Life. Tags: Shapeshifting Prerequisite: Can also reach Natural Fortitude via Grizzly Rage and Lacerate. Passive
Necromancer
Basic Tree
Initiate's Hemorrhage Hemorrhage grants 1.6% of your Maximum Life as Fortify each time it hits an enemy, and has a 1.5% chance per enemy hit to Fortify you for 100% of your Maximum Life. Skill
Core Tree
Supernatural Blood Surge Each time an enemy is hit by Blood Surge's nova, you are Fortified for 1.1% Maximum life. While you have Fortify for over 50% of your Maximum Life, Blood Surge deals x 30% increased damage. Skill
Corpse & Macabre Tree
Drain Vitality Lucky Hit: Hitting enemies with Blood Skills has up to a 30% chance to Fortify you for 2.5% of your Maximum Life. Passive

Fortify Items

The following items either generate Fortify or apply a bonus whilst you are Fortified.

Unique Items

Mutilator Plate

"The Cathedral of Light's earliest attempts at crafting their penitent armor was to infuse the plate with painful blood magic, before such acts were deemed heretical." - Barrett's Book of Implements

Type: Unique Chest Armor
Class: Necromancer

Description: You are Blood Lanced, and when Blood Lance would deal damage to you, it instead Fortifies you for [1.0 - 4.0]% of your Maximum Life and has a 10% chance to form a Blood Orb. Blood Lance deals [10 - 40]%[x] increased damage.

Affixes: (Item Power 925)

[13.0 - 17.5]% Damage Reduction from Enemies Affected by Blood Skills
[13.0 - 17.5]% Maximum Life
+[2 - 4] to Blood Lance
+[46.5 - 60.0]% Blood Lance Duration

Insatiable Fury

When the Days of Ash began, the great druid Nafain reminded his disciples that nothing, not even the loss of their humanity, was too great a sacrifice to protect Túr Dúlra from Astaroth's flames.

Type: Unique Chest Armor
Class: Druid

Description: Werebear form is now your true form, and you gain [2 - 5] Ranks to all Werebear Skills.

Affixes: (Item Power 925)

[8.0 - 12.5]% Maximum Life
+[2.5 - 4.0]% to Ursine Strength's Bonuses
+[3 - 4] to Iron Fur
+[108.5 - 140.0]% Werebear Overpower Damage

Vasily's Prayer

"Roots from the Great Oak growing at the seaward statue of Vasily will, on rare occasions, be found twisted back upon themselves, suffused with ferocious magic." - Barrett's Book of Implements

Type: Unique Helm
Class: Druid

Description: Your Earth Skills are now also Werebear Skills and Fortify you for [2.0 - 5.0]% of your Maximum Health.

Affixes: (Item Power 925)

+[638 - 873] Maximum Life
+[3.1 - 7.3]% Willpower
+[3 - 4] to Defensive Posture
+[1,500 - 1,750] Armor

Legendary Aspects

Assimilation Aspect	Resource	You have 8%[+] increased Dodge Chance. When you Dodge, Fortify for [5 - 10]% of your Maximum Life. Helm, Chest, Pants, Ring, Amulet (+50%)	N/A	Extraction	All
Aspect of Numbing Wrath	Defensive	Each point of Fury generated while at Maximum Fury grants [21 - 41] Fortify. Helm, Chest, Pants, Shield, Amulet (+50%)	Heathen's Keep (Map)	Hawezar	Barbarian
Aspect of Tempering Blows	Defensive	After swapping weapons 5 times, gain [689 - 1,724] Fortify. Helm, Chest, Pants, Shield, Amulet (+50%)	Defiled Catacomb (Map)	Fractured Peaks	Barbarian
Steadfast Berserker's Aspect	Defensive	Gain [1,172 - 2,206] Fortify whenever you deal direct damage while Berserking. Helm, Chest, Pants, Shield, Amulet (+50%)	N/A	Extraction	Barbarian
Aspect of Retaliation	Offensive	Your Core Skills deal up to [25 - 40]%[x] increased damage based on your amount of Fortify.. Gloves, Offhand, 1H Weapon, 2H Weapon (+100%), Ring, Amulet (+50%)	Seaside Descent (Map)	Dry Steppes	Druid
Ballistic Aspect	Utility	When you have Fortify your Earth Skills gain +2 Ranks. Helm, Chest, Gloves, Boots, Shield, Amulet (+50%)	Whispering Pines (Map)	Scosglen	Druid
Skinwalker's Aspect	Defensive	When you use a Shapeshifting Skill that changes your form, Heal for [5 - 20]% of your Maximum Life. If you are at full Life, gain the same amount as Fortify. Helm, Chest, Pants, Shield, Amulet (+50%)	Fading Echo (Map)	Kehjistan	Druid

Tempering Manuals

Blood Finesse Magic	Offensive	+7.0 - 9.0% Blood Attack Speed +10.5 - 15.0% Blood Damage +31.5 - 45.0% Blood Overpower Damage +13.0 - 17.5% Damage while Fortified Weapons, Gloves, Rings, and Amulets.	Necromancer
Blood Finesse Rare	Offensive	+8.0 - 10.0% Blood Attack Speed +21.0 - 30.0% Blood Damage +67.5 - 90.0% Blood Overpower Damage +26.0 - 35.0% Damage while Fortified Weapons, Gloves, Rings, and Amulets.	Necromancer
Blood Finesse Legendary	Offensive	+9.0 - 11.0% Blood Attack Speed +46.5 - 60.0% Blood Damage +144.5 - 185.0% Blood Overpower Damage +52.0 - 70.0% Damage while Fortified Weapons, Gloves, Rings, and Amulets.	Necromancer
Thorn Army Magic	Utility	+7.0 - 9.0% Thorns while Fortified Minions Inherit +5.5 - 7.5% of Your Thorns Skeletal Warriors Inherit +8.0 - 10.0% of Your Thorns Skeletal Mages Inherit +8.0 - 12.5% of Your Thorns Golems Inherit +13.0 - 17.5% of Your Thorns Helms, Chest Armor, Gloves, Pants, Boots, Shields, and Amulets.	Necromancer
Thorn Army Rare	Utility	+8.0 - 10.0% Thorns while Fortified Minions Inherit +8.0 - 10.0% of Your Thorns Skeletal Warriors Inherit +8.0 - 12.5% of Your Thorns Skeletal Mages Inherit +10.5 - 15.0% of Your Thorns Golems Inherit +15.5 - 20.0% of Your Thorns Helms, Chest Armor, Gloves, Pants, Boots, Shields, and Amulets.	Necromancer
Thorn Army Legendary	Utility	+9.0 - 11.0% Thorns while Fortified Minions Inherit +8.0 - 12.5% of Your Thorns Skeletal Warriors Inherit +10.5 - 15.0% of Your Thorns Skeletal Mages Inherit +13.0 - 17.5% of Your Thorns Golems Inherit +13.5 - 22.5% of Your Thorns Helms, Chest Armor, Gloves, Pants, Boots, Shields, and Amulets.	Necromancer
Thorn Body Legendary	Utility	+9.0 - 11.0% Thorns while Fortified +1 - 2 to Outburst +1 - 2 to Tough as Nails Helms, Chest Armor, Gloves, Pants, Boots, Shields, and Amulets.	Barbarian
Thorn Body Rare	Utility	+8.0 - 10.0% Thorns while Fortified +1 to Outburst +1 to Tough as Nails Helms, Chest Armor, Gloves, Pants, Boots, Shields, and Amulets.	Barbarian

Paragon Glyphs


	Battle-Hardened Magic: Barbarian / Druid / Necromancer Bonus: For every 5 Willpower (Barb/Necro) / Intelligence (Druid) purchased within range, you gain + 0.8% increased damage while Fortified.
	Blood-Drinker Rare: Necromancer Bonus: Grants 30% bonus to all Magic nodes within range.	Additional Bonus: Blood Orbs Fortify you for 10% of your Maximum Life. Requirements: 40 Intelligence (in radius range)
	Exhumation Rare: Necromancer Bonus: For every 5 Intelligence purchased within range, your Corpse Skills deal + 3.3% (lvl 1) - 14% (lvl 21) increased damage.	Additional Bonus: Consuming a Corpse Fortifies you for 4% of your Maximum Life and grants 4% Damage Reduction for 4 seconds. Requirements: 40 Intelligence (in radius range)
	Undaunted Rare: Barbarian / Druid / Necromancer Bonus: For every 5 Willpower (Barb, Necro) / Intelligence (Druid) purchased within range, you deal + 2% (lvl 1) - 10% (lvl 21) increased damage while Fortified.	Additional Bonus: You gain 10% Damage Reduction the more Fortify you have. Requirements: 25 Willpower (Barb, Necro) / Intelligence (Druid) (in radius range)

Name	Description
Fortify	Fortified characters take 15% reduced damage. You become Fortified when you have more Fortify than your current Life.

In-game Tooltip.

Changes to Fortify

Patch 1.4.0, May 14, 2024

Damage Reduction granted by Fortify has been increased from 10% to 15%.