Armor

Armor is an attribute shared by all units. Armor is used to determine the amount of damage reduction (or amplification if an armor value is negative) a unit takes from physical damage sources. Higher armor values reduce more damage. Armor is increased by agility, certain abilities and talents, as well as some items. Most items in the armor shop provide armor bonuses.

Main armor

Main armor is the armor value shown in white numbers below the shield icon in the HUD, consisting of base armor and the armor granted by a hero's agility. The only way to improve a hero's main armor is to increase its agility.

The formula to calculate a hero's main armor is:

main armor = base armor + (agility * (1 / 5.9999999999999)).

Base armor

Base armor is the part of the main armor that never changes throughout a game. It consists of one fixed value set for each unit individually. The base armor of a unit can be a negative number. Since only heroes have agility, the HUD of all non-hero units shows their base armor.

The base armor of heroes can be calculated with this formula:

base armor = main armor - (agility * (1 / 5.9999999999999)).

Armor granted by agility

The sum of agility points a hero has is multiplied by (1 / 5.9999999999999) and added on top of the base armor to define the main armor value. Agility can be increased by acquiring levels, as well as specific abilities, items and talents.

Armor of heroes

Hero Armor

Hero Base Level 1 Level 15 Level 25 Level 30 Abaddon 0 3.83 6.87 9.03 10.12 Alchemist 0 3.67 7.17 9.67 10.92 Ancient Apparition -1 2.33 7.47 11.13 12.97 Anti-Mage 1 5 11.53 16.2 18.53 Arc Warden 0 3.33 10.33 15.33 17.83 Axe -1 2.33 6.3 9.13 10.55 Bane 1 4.83 10.67 14.83 16.92 Batrider 2 4.5 7.77 10.1 11.27 Beastmaster -1 2 5.73 8.4 9.73 Bloodseeker 2 6 13.23 18.4 20.98 Bounty Hunter 5 8.5 14.57 18.9 21.07 Brewmaster 0 3.17 7.83 11.17 12.83 Bristleback 1 3.83 8.03 11.03 12.53 Broodmother -1 2 8.07 12.4 14.57 Centaur Warrunner -2 0.5 2.83 4.5 5.33 Chaos Knight 2 5 8.27 10.6 11.77 Chen -1 1.5 6.4 9.9 11.65 Clinkz 0 4.17 10.47 14.97 17.22 Clockwerk 1 3.17 8.07 11.57 13.32 Crystal Maiden 0 2.67 6.4 9.07 10.4 Dark Seer 2 5.17 9.37 12.37 13.87 Dark Willow 0 3 6.03 8.2 9.28 Dawnbreaker 2 4.33 8.3 11.13 12.55 Dazzle 0 3.33 6.6 8.93 10.1 Death Prophet 1 3.67 8.33 11.67 13.33 Disruptor 0 2.5 5.77 8.1 9.27 Doom 2 4.5 8 10.5 11.75 Dragon Knight 0 2.67 7.33 10.67 12.33 Drow Ranger 0 3.33 10.1 14.93 17.35 Earth Spirit 0 2.83 8.43 12.43 14.43 Earthshaker 2 4 7.27 9.6 10.77 Elder Titan 0 2.67 6.87 9.87 11.37 Ember Spirit 0 3.67 11.13 16.47 19.13 Enchantress 1 4.17 9.07 12.57 14.32 Enigma 1 3.33 5.67 7.33 8.17 Faceless Void 0 3.17 10.17 15.17 17.67 Grimstroke 0 3 7.43 10.6 12.18 Gyrocopter 2 6.33 13.57 18.73 21.32 Hoodwink 0 4 12.4 18.4 21.4 Huskar -1 0.67 4.17 6.67 7.92 Invoker -1 1.33 5.53 8.53 10.03 Io 1 3.33 7.07 9.73 11.07 Jakiro 1 3.5 6.3 8.3 9.3 Juggernaut 0 5.67 12.2 16.87 19.2 Keeper of the Light 0 2.5 6.23 8.9 10.23 Kunkka 2 4.33 8.07 10.73 12.07 Legion Commander 0 3 6.97 9.8 11.22 Leshrac 0 3.83 10.37 15.03 17.37 Lich -1 1.83 6.5 9.83 11.5 Lifestealer 1 4.17 10.23 14.57 16.73 Lina 0 3.83 9.43 13.43 15.43 Lion 0 2.5 6 8.5 9.75 Lone Druid 0 3.33 8 11.33 13 Luna 2 6 13.93 19.6 22.43 Lycan 0 3 7.2 10.2 11.7 Magnus 1 2.5 7.17 10.5 12.17 Marci 0 3.33 7.53 10.53 12.03 Mars -1 2.33 6.3 9.13 10.55 Medusa -1 2.67 11.07 17.07 20.07 Meepo 4 6.83 11.73 15.23 16.98 Mirana -2 2 7.83 12 14.08 Monkey King 2 5.83 14.47 20.63 23.72 Morphling -2 2 11.1 17.6 20.85 Muerta -1 2.33 8.63 13.13 15.38 Naga Siren 1 4.5 12.2 17.7 20.45 Nature's Prophet 0 2.33 9.8 15.13 17.8 Necrophos 2 4 7.03 9.2 10.28 Night Stalker 2 5 10.13 13.8 15.63 Nyx Assassin 1 4 9.83 14 16.08 Ogre Magi 4 6.33 9.83 12.33 13.58 Omniknight 2 4.5 9.17 12.5 14.17 Oracle 1 3.5 7.47 10.3 11.72 Outworld Destroyer 2.5 6.17 9.9 12.57 13.9 Pangolier 2 5 10.83 15 17.08 Phantom Assassin 1 4.5 12.43 18.1 20.93 Phantom Lancer -1 3.33 9.87 14.53 16.87 Phoenix -1 1 4.5 7 8.25 Primal Beast 2 4.5 6.83 8.5 9.33 Puck -3 0.67 6.5 10.67 12.75 Pudge -1 1.33 4.6 6.93 8.1 Pugna 0 3.5 6.53 8.7 9.78 Queen of Pain 0 3.67 9.5 13.67 15.75 Razor 0 4 10.53 15.2 17.53 Riki 0 5 10.6 14.6 16.6 Rubick 1 4.83 10.67 14.83 16.92 Sand King 1 4.17 8.37 11.37 12.87 Shadow Demon 0 3 8.13 11.8 13.63 Shadow Fiend 1 5.17 13.33 19.17 22.08 Shadow Shaman 3 5.67 9.4 12.07 13.4 Silencer 0 3.67 9.27 13.27 15.27 Skywrath Mage -2 0.17 2.03 3.37 4.03 Slardar 3 5.83 11.43 15.43 17.43 Slark 0 3.5 7 9.5 10.75 Snapfire 1 3.67 6.47 8.47 9.47 Sniper -1 3.5 10.97 16.3 18.97 Spectre 0 4.17 9.07 12.57 14.32 Spirit Breaker 1 3.83 7.8 10.63 12.05 Storm Spirit 1 4.67 10.73 15.07 17.23 Sven -1 2.5 7.63 11.3 13.13 Techies 2 4.33 7.37 9.53 10.62 Templar Assassin 0 3.83 11.3 16.63 19.3 Terrorblade 5 8.67 18 24.67 28 Tidehunter 0 2.5 6 8.5 9.75 Timbersaw 0 2.67 5.7 7.87 8.95 Tinker 2 4.83 8.1 10.43 11.6 Tiny 0 0 0 0 0 Treant Protector -1 1.5 5.7 8.7 10.2 Troll Warlord -1 2.83 10.53 16.03 18.78 Tusk 1 4.83 9.73 13.23 14.98 Underlord 3 5 8.73 11.4 12.73 Undying 1 2.67 5.47 7.47 8.47 Ursa 1 4 10.53 15.2 17.53 Vengeful Spirit 0 3.5 8.4 11.9 13.65 Venomancer 0 4 8.67 12 13.67 Viper -2 1.5 7.8 12.3 14.55 Visage -1 0.83 3.17 4.83 5.67 Void Spirit -1 2.17 7.3 10.97 12.8 Warlock 1 2.67 5 6.67 7.5 Weaver 1 3.83 11.07 16.23 18.82 Windranger 0 3.17 6.43 8.77 9.93 Winter Wyvern 1 3.67 7.17 9.67 10.92 Witch Doctor 0 2.17 5.43 7.77 8.93 Wraith King -1 1.67 5.63 8.47 9.88 Zeus 2 3.83 6.63 8.63 9.63

Bonus armor

Bonus armor is the armor value shown in green numbers with a plus on the left, right below the white armor number on a unit's statistics. Whenever an item or skill shows a +armor value, e.g. Blade Mail (+6 Armor), it increases the bonus armor of the affected unit. Probably the most important difference between main and bonus armor is that illusions only benefit from main armor, although their HUD still shows the bonus armor just like on other heroes, to make them less obvious to the enemy. Some spells like Natural Order also only affect main armor.

Armor manipulation

Armor increasing abilities

The following abilities are able to increase unit's armor:

Unit abilities

• Ancient Black Dragon - Dragonhide Aura
  
  Radius: {{#show:Ancient Black Dragon#Dragonhide Aura|?value1#}}
  Armor Bonus: {{#show:Ancient Black Dragon#Dragonhide Aura|?value2#}}
  Aura, buffs all allies within range. Buff lingers for a short while. Stack with itself.
• Axe - Berserker's Call
  
  Armor Bonus: {{#show:Axe#Berserker's Call|?value2#}}
  Duration: {{#show:Axe#Berserker's Call|?value3#}}
  Buffs Axe upon cast.
• Dazzle - [[Dazzle#|]]
  64px|text-top|link=Dazzle#
  Radius: {{#show:Dazzle#Weave|?value2#}}
  Armor Bonus per Second: {{#show:Dazzle#Weave|?value3#}}
  Duration: {{#show:Dazzle#Weave|?value4#}}
  Buffs all allies within the area upon cast.
• Dragon Knight - Dragon Blood
  
  Armor Bonus: {{#show:Dragon Knight#Dragon Blood|?value2#}} ( {{#show:Dragon Knight#Dragon Blood|?value2 tal#}})
  Passive, permanent bonus.
• Drow Ranger - Marksmanship
  
  Armor Bonus: ( )
  Increases armor by granting agility. Bonuses are temporarily lost when enemy heroes get too close.
• Lich - [[Lich#|]]
  64px|text-top|link=Lich#
  Armor Bonus: {{#show:Lich#Ice Armor|?value2#}}
  Building Armor Bonus: {{#show:Lich#Ice Armor|?value3#}} ( {{#show:Lich#Ice Armor|?value3 tal#}})
  Duration: {{#show:Lich#Ice Armor|?value6#}}
  Buffs the target upon cast.
• Lone Druid - [[Lone Druid#|]]
  64px|text-top|link=Lone Druid#
  Radius: {{#show:Lone Druid#Battle Cry|?value1#}}
  Armor Bonus: {{#show:Lone Druid#Battle Cry|?value3#}}
  Duration: {{#show:Lone Druid#Battle Cry|?value4#}}
  Buffs all of Lone Druid's units within range upon cast.
• Lone Druid - True Form
  
  Armor Bonus: {{#show:Lone Druid#True Form|?value3#}}
  Increases armor until transforming back.
• Monkey King - Wukong's Command
  
  Armor Bonus: {{#show:Monkey King#Wukong's Command|?value10#}} ( {{#show:Monkey King#Wukong's Command|?value10 tal#}})
  Max Duration: {{#show:Monkey King#Wukong's Command|?value11#}}
  Increases armor as long as Monkey King can maintain Wukong's Command.
• Morphling - Attribute Shift (Agility Gain)
  
  Base Armor Bonus:
  Shifted Armor Bonus: 0.17 per shifted strength to agility.
  
• Ogre Frostmage - Ice Armor
  
  Armor Bonus: {{#show:Ogre Frostmage#Ice Armor|?value2#}}
  Duration: {{#show:Ogre Frostmage#Ice Armor|?value5#}}
  Buffs the target upon cast.
• Roshan - Strength of the Immortal
  
  Armor Bonus per {{#show:Roshan#Strength of the Immortal|?value1#}} Minutes: {{#show:Roshan#Strength of the Immortal|?value2#}}
  Passive, increases Roshan's armor as time goes by.
• Slark - Essence Shift
  
  Armor Bonus: 0.17 per converted agility
  Stack Duration: {{#show:Slark#Essence Shift|?value3#}}
  Steals 1 of each stats from attack targets and converts them into agility for self. The stacks' durations are independent from each other.
• Sven - Warcry
  
  Radius: {{#show:Sven#Warcry|?value1#}}
  Armor Bonus: {{#show:Sven#Warcry|?value3#}}
  Duration: {{#show:Sven#Warcry|?value4#}}
  Buffs allies within range upon cast.
• Timbersaw - Reactive Armor
  
  Max Stacks: {{#show:Timbersaw#Reactive Armor|?value1#}}
  Armor Bonus per Stack: {{#show:Timbersaw#Reactive Armor|?value3#}}
  Stack Duration: {{#show:Timbersaw#Reactive Armor|?value4#}}
  Passive, grants a stack whenever attacked. The stacks' durations are independent from each other.
• Towers - Tower Protection
  
  Radius: {{#show:Buildings#Tower Protection|?value1#}}
  Armor Bonus (Tier 1): {{#show:Buildings#Tower Protection|?value2#}}
  Armor Bonus (Tier 2/3/4): {{#show:Buildings#Tower Protection|?value3#}}
  
• Troll Warlord - Berserker's Rage
  
  Armor Bonus: {{#show:Troll Warlord#Berserker's Rage|?value1#}}
  Grants armor until toggled off.
• Wildwing Ripper - Toughness Aura
  
  Radius: {{#show:Wildwing Ripper#Toughness Aura|?value1#}}
  Armor Bonus: {{#show:Wildwing Ripper#Toughness Aura|?value2#}}
  Aura, buffs all allies within range. Buff lingers for a short while.

Item abilities

• Assault Cuirass - Assault Aura
  
  Radius: {{#show:Assault Cuirass#Assault Aura|?value1#}}
  Armor Bonus: {{#show:Assault Cuirass#Assault Aura|?value3#}}
  Aura, buffs all allies within range. Buff lingers for a short while.
• Buckler - [[Buckler#|]]
  
  Radius: {{#show:Buckler#Armor Bonus|?value1#}}
  Armor Bonus: {{#show:Buckler#Armor Bonus|?value2#}}
  Hero Duration: {{#show:Buckler#Armor Bonus|?value3#}}
  Non-Hero Duration: {{#show:Buckler#Armor Bonus|?value4#}}
  Buffs allies within range upon cast.
• Crimson Guard - Guard
  
  Radius: {{#show:Crimson Guard#Guard|?value1#}}
  Armor Bonus: {{#show:Crimson Guard#Guard|?value4#}}
  Duration: {{#show:Crimson Guard#Guard|?value5#}}
  Buffs allies within range upon cast.
• Guardian Greaves - Guardian Aura
  
  Radius: {{#show:Guardian Greaves#Guardian Aura|?value1#}}
  Armor Bonus: {{#show:Guardian Greaves#Guardian Aura|?value3#}}
  Boost Health Threshold: {{#show:Guardian Greaves#Guardian Aura|?value4#}}
  Boosted Armor Bonus: {{#show:Guardian Greaves#Guardian Aura|?value6#}}
  Aura, buffs all allies within range. Buff lingers for a short while.
• Medallion of Courage - Valor
  
  Ally Armor Bonus: {{#show:Medallion of Courage#Valor|?value4#}}
  Duration: {{#show:Medallion of Courage#Valor|?value5#}}
  Increases the target ally's armor upon cast.This is an old ability.
• Mekansm - Restore
  
  Radius: {{#show:Mekansm#Restore|?value1#}}
  Armor Bonus: {{#show:Mekansm#Restore|?value3#}}
  Duration: {{#show:Mekansm#Restore|?value4#}}
  Buffs allies within range upon cast.
• Ring of Aquila - Aquila Aura
  
  Radius: {{#show:Ring of Aquila#Aquila Aura|?value1#}}
  Armor Bonus: {{#show:Ring of Aquila#Aquila Aura|?value3#}}
  Aura, buffs all allies within range. Buff lingers for a short while.
• Ring of Basilius - Basilius Aura
  
  Radius: {{#show:Ring of Basilius#Basilius Aura|?value1#}}
  Armor Bonus: {{#show:Ring of Basilius#Basilius Aura|?value3#}}
  Aura, buffs all allies within range. Buff lingers for a short while.
• Solar Crest - Shine
  
  Ally Armor Bonus: {{#show:Solar Crest#Shine|?value5#}}
  Duration: {{#show:Solar Crest#Shine|?value7#}}
  Increases the target ally's armor upon cast.
• Vladmir's Offering - Vladmir's Aura
  
  Radius: {{#show:Vladmir's Offering#Vladmir's Aura|?value1#}}
  Armor Bonus: {{#show:Vladmir's Offering#Vladmir's Aura|?value7#}}
  Aura, buffs all allies within range. Buff lingers for a short while.

Armor reducing abilities

The following abilities are able to reduce unit's armor:

Unit abilities

• Alchemist - Acid Spray
  
  Radius: {{#show:Alchemist#Acid Spray|?value2#}}
  Armor Reduction: {{#show:Alchemist#Acid Spray|?value4#}}
  Spray Duration: {{#show:Alchemist#Acid Spray|?value5#}}
  Aura, debuffs all enemies within range. The debuff lingers for a short while.
• Bristleback - Viscous Nasal Goo
  
  Max Stacks: {{#show:Bristleback#Viscous Nasal Goo|?value3#}} ( {{#show:Bristleback#Viscous Nasal Goo|?value3 tal#}})
  Base Armor Reduction: {{#show:Bristleback#Viscous Nasal Goo|?value4#}}
  Armor Reduction per Stack: {{#show:Bristleback#Viscous Nasal Goo|?value5#}}
  Hero Duration: {{#show:Bristleback#Viscous Nasal Goo|?value8#}}
  Creep Duration: {{#show:Bristleback#Viscous Nasal Goo|?value9#}}
  Applies a debuff on the target upon cast. All stacks expire simultaneously.
• Chaos Knight - Reality Rift
  
  Armor Reduction: {{#show:Chaos Knight#Reality Rift|?value3#}}
  Duration: {{#show:Chaos Knight#Reality Rift|?value4#}}
  Applies a debuff on the target upon cast, before the attack is applied.
• Dazzle - [[Dazzle#|]]
  64px|text-top|link=Dazzle#
  Radius: {{#show:Dazzle#Weave|?value2#}}
  Armor Reduction per Second: {{#show:Dazzle#Weave|?value3#}}
  Duration: {{#show:Dazzle#Weave|?value4#}}
  Debuffs all enemies within the area upon cast.
• Elder Titan - Natural Order
  
  Radius: {{#show:Elder Titan#Natural Order|?value1#}}
  Base Armor Reduction: {{#show:Elder Titan#Natural Order|?value2#}}
  Aura, debuffs all enemies within range. The debuff lingers for a short while. Only reduces base armor and that granted by agility.
• Morphling - Attribute Shift (Strength Gain)
  
  Armor Reduction: 0.17 per shifted agility to strength.
  
• Naga Siren - Rip Tide
  
  Radius: {{#show:Naga Siren#Rip Tide|?value1#}}
  Armor Reduction: {{#show:Naga Siren#Rip Tide|?value3#}}
  Duration: {{#show:Naga Siren#Rip Tide|?value4#}}
  Debuffs all enemies within range upon cast.
• Pangolier - [[Pangolier#|]]
  64px|text-top|link=Pangolier#
  Total Armor Reduction: {{#show:Pangolier#Heartpiercer|?value2#}}
  Duration: {{#show:Pangolier#Heartpiercer|?value5#}}
  Applies a debuff on the target upon proccing. Sets the target's armor to 0, regardless of any bonuses or reductions.
• Phantom Assassin - Talent by Level 15 Right
  
  Armor Corruption: 25
  Applies a debuff on the target upon attack land, before the damage is applied.
• Razor - Eye of the Storm
  
  Strike Interval: {{#show:Razor#Eye of the Storm|?value2#}} ( {{#show:Razor#Eye of the Storm|?value2 aghs#}})
  Armor Reduction per Strike: {{#show:Razor#Eye of the Storm|?value4#}}
  Duration: {{#show:Razor#Eye of the Storm|?value5#}}
  Adds a stack on the attack target upon lightning impact, after the damage is applied. Does not reduce armor of struck buildings. Armor Reduction expires when the storm does.
• Shadow Fiend - Presence of the Dark Lord
  
  Radius: {{#show:Shadow Fiend#Presence of the Dark Lord|?value1#}}
  Armor Reduction: {{#show:Shadow Fiend#Presence of the Dark Lord|?value2#}} ( {{#show:Shadow Fiend#Presence of the Dark Lord|?value2 tal#}})
  Aura, debuffs all enemies which have vision over Shadow Fiend within range. The debuff lingers for a short while.
• Slardar - Corrosive Haze
  
  Armor Reduction: {{#show:Slardar#Corrosive Haze|?value2#}}
  Duration: {{#show:Slardar#Corrosive Haze|?value3#}}
  Debuffs the target upon cast.
• Slark - Essence Shift
  
  Armor Reduction: 0.17 per lost agility
  Steals 1 of each stat from attack target and converts them into agility for self. The stacks' durations are independent from each other.
• Templar Assassin - Meld
  
  Armor Reduction: {{#show:Templar Assassin#Meld|?value3#}}
  Duration: {{#show:Templar Assassin#Meld|?value4#}}
  Debuffs the attack target upon projectile impact, after the attack damage is applied, but before Meld damage is applied.
• Tidehunter - Gush
  
  Armor Reduction: {{#show:Tidehunter#Gush|?value5#}} ( {{#show:Tidehunter#Gush|?value5 tal#}})
  Duration: {{#show:Tidehunter#Gush|?value7#}}
  Debuffs the target upon projectile impact.
• Timbersaw - Whirling Death
  
  Radius: {{#show:Timbersaw#Whirling Death|?value1#}}
  Primary Attribute Reduction: {{#show:Timbersaw#Whirling Death|?value3#}} ( {{#show:Timbersaw#Whirling Death|?value3 tal#}}) (0.17 armor lost per point of agility reduced)
  Duration: 7
  All affected agility heroes lose agility, and therefore lose armor for the duration.
• Vengeful Spirit - Wave of Terror
  
  Travel Distance: {{#show:Vengeful Spirit#Wave of Terror|?value2#}}
  Radius: {{#show:Vengeful Spirit#Wave of Terror|?value3#}}
  Armor Reduction: {{#show:Vengeful Spirit#Wave of Terror|?value5#}}
  Duration: {{#show:Vengeful Spirit#Wave of Terror|?value6#}}
  Debuffs all hit enemies.
• Weaver - The Swarm
  
  Attack Interval: {{#show:Weaver#The Swarm|?value8#}}
  Armor Reduction per Attack: {{#show:Weaver#The Swarm|?value10#}}
  Duration: {{#show:Weaver#The Swarm|?value11#}}
  Adds a stack on affected units on each interval, before the damage is applied. Armor reduction lasts as long as the beetle does or until it is killed.
• Ancient Prowler Shaman - Desecrate
  
  Radius: {{#show:Ancient Prowler Shaman#Desecrate|?value1#}}
  Base Armor Reduction: {{#show:Ancient Prowler Shaman#Desecrate|?value3#}}
  Duration: {{#show:Ancient Prowler Shaman#Desecrate|?value4#}}
  Debuffs all enemies within range upon cast. Only reduces base armor and that granted by agility.This is an old ability.
• Forged Spirit - Melting Strike
  
  Armor Reduction per Attack: {{#show:Forged Spirit#Melting Strike|?value1#}}
  Armor Reduction Cap: {{#show:Forged Spirit#Melting Strike|?value2#}}
  Duration: {{#show:Forged Spirit#Melting Strike|?value3#}}
  Debuffs the attack target upon projectile impact, after the attack damage is applied. The stacks expire simultaneously.

Item abilities

• Assault Cuirass - Assault Aura
  
  Radius: {{#show:Assault Cuirass#Assault Aura|?value1#}}
  Armor Reduction: {{#show:Assault Cuirass#Assault Aura|?value4#}}
  Aura, debuffs all enemies within range. Debuff lingers for a short while.
• Blight Stone - Lesser Corruption
  
  Armor Reduction: {{#show:Blight Stone#Lesser Corruption|?value1#}}
  Duration: {{#show:Blight Stone#Lesser Corruption|?value2#}}
  Debuffs the attack target upon attack/projectile, before the attack damage is applied.
• Desolator - Corruption
  
  Armor Reduction: {{#show:Desolator#Corruption|?value1#}}
  Duration: {{#show:Desolator#Corruption|?value2#}}
  Debuffs the attack target upon attack/projectile, before the attack damage is applied.
• Mask of Madness - Berserk
  
  Armor Reduction: {{#show:Mask of Madness#Berserk|?value3#}}
  Duration: {{#show:Mask of Madness#Berserk|?value4#}}
  Applies the armor reduction on the caster in the form of a buff, so it cannot be removed with allied dispels.
• Medallion of Courage - Valor
  
  Armor Reduction: {{#show:Medallion of Courage#Valor|?value3#}}
  Duration: {{#show:Medallion of Courage#Valor|?value5#}}
  Debuffs the caster and the target enemy upon cast. Also debuffs self when targeting allies.This is an old ability.
• Solar Crest - Shine
  
  Armor Reduction: {{#show:Solar Crest#Shine|?value3#}}
  Duration: {{#show:Solar Crest#Shine|?value7#}}
  Debuffs the caster and the target enemy upon cast. Also debuffs self when targeting allies.

Armor granting items

The following items increase a unit's Armor. The effects are limited to the item's owner, which must have the item equipped.

Damage multiplier

All units, including buildings, have an inherent base armor value and armor type. Any physical damage dealt to a unit is multiplied by the damage multiplier, resulting in either damage reduction or increase depending on the target's armor value. {{#set:armor=0.05}} For any real-valued armor, the damage multiplier is defined as

damage multiplier = 1 - ({{#show:Armor|?armor#}} × armor ÷ (1 + {{#show:Armor|?armor#}} × |armor|)).

In Dota 2, the damage multiplier limits are 2 and 0, for infinitely negative and positive armor, respectively.

Examples

Armor	Damage multiplier	Armor	Damage multiplier
1	%	-1	%
2	%	-2	%
5	%	-5	%
10	%	-10	%
15	%	-15	%
20	%	-20	%

Effective HP

Relationships between effective HP %, damage multiplier and armor

Armor values can be understood by either adjusting incoming damage (multiplying physical damage by the damage multiplier), or adjusting health (dividing health by the damage multiplier, a quantity defined as the effective HP).

For positive armor values, a unit gains effective HP equal to % of their base health per armor point. For example, a hero with base HP of 1000 has 1000 effective HP at 0 armor and 1500 effective HP at 10 armor, an increase of %. For negative armor values, the effective HP reduction diminishes with decreasing armor, trending towards 50%.

Armor	-40	-30	-20	-10	0	10	20	30	40
Effective HP

This definition of effective HP assumes all damage taken is physical. In Dota 2, magical damage (such as Lina's or Lion's ultimate) is modified by magic resistance.

Calculating effective HP:

Method 1 (the definition above):

effective HP = base HP ÷ damage multiplier

Method 2 (obtained by assuming the sign of the armor value and combining fractions):

• If armor is positive,

effective HP = base HP × (1 + {{#show:Armor|?armor#}} × armor)

• If armor is negative,

effective HP = base HP × (1 - {{#show:Armor|?armor#}} × armor) ÷ (1 - 2 × {{#show:Armor|?armor#}} × armor)

Example 1:

A level 25 Sven has a total HP of 2293.6 and 11.3 points of armor. What is his effective HP vs physical damage?

By method 1, EHP = 2293.6 ÷ ( 1 - (11.3 × {{#show:Armor|?armor#}}) ÷ (1 + 11.3 × {{#show:Armor|?armor#}}) ) = 2293.6 ÷ =

By method 2, as his armor is positive, EHP = 2293.6 × (1 + {{#show:Armor|?armor#}} × 11.3) = 2293.6 × =

Sven can tank physical damage.

Example 2:

The same Sven from previous example is hit by a maxed Corrosive Haze. His armor is now . What is his effective HP vs physical damage?

By method 1, EHP = 2293.6 ÷ ( 1 - ( × {{#show:Armor|?armor#}}) ÷ (1 + × {{#show:Armor|?armor#}}) ) = 2293.6 ÷ =

By method 2, as his armor is negative, EHP = 2293.6 × (1 - {{#show:Armor|?armor#}} × ) ÷ (1 - (2 × {{#show:Armor|?armor#}} × )

Sven can tank physical damage.

Armor types

There are several different types of armor, which determine how much damage a unit takes against certain attack damage types. Each of the 3 different armor types either reduces, increases or does not affect the damage from each of the damage types, on top of armor values manipulating them.

Example:

A hero with 100 attack damage attacking a siege unit which has 0 armor deals 50 damage to it, because the attack type "hero" deals 50% less damage against the armor type "structure", which is the siege creeps' and all buildings' armor type. If the siege creep would gain 5 armor, the 100 damage attack would deal (100 * * 0.5) = damage. The same attack would deal damage to a unit with any other armor type, since attack type hero deals full damage to them.

This table shows how much damage each armor type reduces against each attack damage type and which unit uses which armor type (units which take a set amount of damage per attack are excluded).

Armor Type	Used by	Attack Damage Type
		Hero	Basic	Pierce	Siege
Hero		100%	75%	50%	85%
Basic		100%	100%	150%	100%
Structure		50%	70%	35%	250%

Trivia

• In DotA the base magic resistance was bound to the assigned armor. In case of Hero Armor only 75% of the magic damage was applied. Some heroes possessed hidden passive skills to alter their base magic susceptibility albeit Hero Armor to 90% ( Visage) or 65% ( Meepo). Nowdays in Dota 2 magic resistance works independently from armor.
• The Basic armor type was refered to as Medium armor in DotA.
• The deprecated Light damage type used to be called Chaos damage in DotA.
• The deprecated Weak armor type used be called Light armor, Soft was referred to as Unarmored, and Strong was known as Heavy armor type.

Negative armor disparity

Negative armor damage multiplier for DotA and Dota 2

This graph shows how much more additional damage a target takes when armor debuffs are applied, using the WC3 DotA armor formula.

Amplified damage from negative armor is calculated differently in WC3 DotA than in Dota 2..

Negative armor in WC3 DotA has a cap of -20 armor (71% damage increase). Further reducing the armor does not change the damage increase.. Also, the more aggressive damage amplify formula is used resulting in a max damage increase of 71 %. The amplified damage is calculated from this formula:

Damage increase = 1 - 0.94^(-armor)

Comparison table

Armor	WC3 DotA Damage amplification	Dota 2 Damage amplification	Relative difference
0	0.0 %	0.0 %	N/A
-5	26.6 %	%	%
-10	46.1 %	%	%
-20	71.0 %	%	%
-40	71.0 %	%	%
-60	71.0 %	%	%

Balance changelog

See Damage#Balance changelog

See also

• Damage manipulation
• Magic resistance
• Agility

References

Mechanics Main Heroes Unit Type (Heroes / Clones / Illusions) Complexity Attributes Table Buyback Level Roles Gold Experience Animations Stats Armor Attributes ( Strength / Agility / Intelligence) / Universal) Health & Mana (HP Regen & MP Regen) Magic Resistance Movement Speed / Slow Resistance Status Resistance Turn Rate Misc Creep Controling Death / Denying Vision Unit Size (Collision Size / Bound Radius / Selection Box / Model Size) Gib Type / Shades Adjectives Buildings Towers / Barracks / Ancient / Fountain Effigy Neutral Buildings (Outposts / Watchers / Twin Gates / Lotus Pools) Abilities Type Active / Passive / Autocast Aura Accuracy / Evasion Channeling Damage Barrier Damage Block Damage Manipulation Damage Over Time Talents Teleport Targeting Area No Target Point Unit Vector Combinations Casting Cast Range / Motion Buffer Cast Animation (Cast Point + Backswing) Cooldown Reduction (Flat / Current Flat / Percentage) Reset Charge-based Runes Bounty Rune Water Rune Wisdom Rune Power Runes ( Amplify Damage Rune / Arcane Rune / Haste Rune / Illusion Rune / Invisibility Rune / Regeneration Rune / Shield Rune) Misc Random Distribution Transformation Attack Damage Attack Damage Instant Attack Heroes Attack Classes Attack Range (Acquisition Range) Attack Speed (BAT / Interval) Damage Types (Physical / Magical / Pure / Instant Kill) Flags (HP Removal / No-reflection / No-Spell-Lifesteal / No-Spell-Amplification) Projectile Speed Spell Damage (Outgoing / Incoming) Modifiers Bash Cleave / Splash Corruption Critical Strike Lifesteal / Spell Lifesteal Mana Break On-hit Effects Misc Damage Instance Animation / Orb Walking Status Effects Disables Cyclone Disabling Orders Forced Movement (Knockback) / Upward Movement Fear (Hypnosis) Hide Hex Root Leash Stun Sleep Taunt Movement Move Speed Slow Flying Movement Phased / Tree Walk / Unobstructed Movement Other Attack Immune / Non-targetable Attack Speed Slow Debuff Immunity Spell Immunity Invulnerability Invisibility Blind Break Disarm Ethereal Silence Mute Trap Dispels Basic Strong Death Items Mechanics Courier Sharing / Selling Disassemble Recipes Neutral Item Drop