Damage Engine

This bundle is marked as director's cut. It exceeds all expectations and excels in every regard.
Damage Engine

Three GUI Damage systems for the community of The Hive,
Seven vJass Damage systems for the JASS-heads on their pedestals high,
Nine competing Damage systems, doomed to die,
One for Bribe on his dark throne
In the Land of the Hive where the Workshop lies.
One Damage Engine to rule them all, One Damage Engine to find them,
One Damage Engine to bring them all and in cross-compatibility unite them.

Whether you're looking for a simple DDS (Damage Detection System), need to modify damage or even if you want a complex network of damage pre-and post-processing, this resource is for you. Damage Engine is the most adapted DDS in existence to take full advantage of the new damage detection natives, and is constantly evaluated and scrutinized by both the community and myself for performance improvements, bug fixes and new features alike.

What started with humble beginnings to bring a Unit Indexer-based version of DDS to GUI users to improve on the previous standard (at the time it was Weep's GDDS) would eventually evolve to incorporate other aspects of damage systems out there. @looking_for_help had identified an extremely useful technique with negative spell resistance being used to detect spell damage, and for a time his Physical Damage Detection system became the new standard. It wouldn't be until much later when Damage Engine would resurface and use the same technique in order to be more useful for the community.

Fast forward to 2020, and you'll find not only that cross-compatibility with Weep's and LFH's systems are incorporated, but the most popular DDS systems in existence - even vJass ones - are fully supported via stripped-down API wrappers. All of the functionality of prior DDS systems has been infused into Damage Engine 5.7, and as such the transition to a "one size fits all" DDS is complete. I hope you find this to be useful, and I also hope that it will help you in developing your map to be more dynamic what than you had previously thought possible.


Legacy Code & Requirements

How it works

How to install/upgrade

Video Guides



  • Damage Type, Attack Type, Weapon Type, Armor Type and Defense Type detection and modification to alter/understand the fundamentals of WarCraft 3's damage processing;
  • Access to the view and change the damage amount before and/or after reduction by armor, armor type and shields.
  • Fully cross-compatible with every major DDS - vJass and GUI alike.
  • Correctly distribute/negate Spirit Link damage.
  • Differentiate between Ranged, Melee, Spell or other types of attack.
  • Does not require any Object Editor data nor Unit Indexer.
  • As of 5.4, it is now completely recursion-proof.
  • Other features:
    • Damage Blocking, reducing, amplifying and/or conversion to healing
    • Does not require you to know nor use Jass NewGen Pack nor any custom script
    • Custom DamageType association available to be set before and/or during damage event
    • Detect when multiple targets were hit simultaneously via DamageEventAOE > 1.
    • Detect when the same unit was hit simultaneously by the same source via DamageEventLevel > 1.
  • Detect damage: use the event "OnDamageEvent Equal to <any value>". You have access to the following variables for reference:
    • DamageEventSource - the unit dealing the damage
    • DamageEventTarget - the unit receiving the damage
    • DamageEventAmount - the amount of damage the unit will receive
    • DamageEventPrevAmt - the amount of damage prior to being modified by the game engine.
    • DamageEventAttackT - the attack type (Chaos, Spells, Pierce, etc.)
    • DamageEventDamageT - the damage type - for comprehensive info, click here.
    • DamageEventWeaponT - the weapon type determines if an attack plays some kind of sound on attack (ie. Metal Heavy Bash). It is always NONE for spells and almost always NONE for ranged attacks.
    • DamageEventArmorT - the armor type (Flesh, Stone, Ethereal, etc.)
    • DamageEventDefenseT - the defense type (Hero, Fortified, Unarmored, etc.)
    • DamageEventArmorPierced - if DAMAGE_TYPE_NORMAL, how much armor was set to be ignored by the user.
    • IsDamageSpell, IsDamageRanged, IsDamageMelee - determine the source category of damage dealt.
    • IsDamageCode - Determine if the damage was dealt natively or by the user. This can give incorrect readings if the user has not identified to Damage Engine that it is code damage. Therefore I recommend setting NextDamageType prior to dealing damage.
    • DamageEventType - An integer identifier that can be referenced by you for whatever extra differentiation you need. You can also create your own special damage types and add them to the definitions in the Damage Event Config trigger. If you the unit should explode on death by that damage, use a damage type integer less than 0. If you want the damage to ignore all modifications, use DamageTypePure.
  • To change damage before it's processed by the WarCraft 3 engine: use the event "PreDamageEvent Becomes Equal to <any value>". Whether you just want to use one monolithic trigger for all damage modification like I do in the demo map, or use the different modifier events here, is up to you.
  • To interact with damage after it's been factored for armor and resistances, use "ArmorDamageEvent Becomes Equal to <any value>". This is typically useful for custom shields. If you fully block or absorb DamageEventAmount (setting it to 0 or less), this event doesn't run.
  • To set the DamageEventType before dealing triggered Damage, use:
    - Set NextDamageType = DamageTypeWhatever
    - Unit - Cause...
  • You can modify the following variables from a "PreDamageEvent" trigger:
    • DamageEventAmount
    • DamageEventAttackT/DamageT/WeaponT/ArmorT/DefenseT
    • DamageEventArmorPierced
    • DamageEventType
    • DamageEventOverride - You can set this if you want to remind yourself not to modify the damage further. If you use the UNKOWN damage type from a Unit - Damage Target native or set "NextDamageType = DamageTypePure" before that function, damage modification is skipped.
  • To catch a unit the moment before it would die from damage, use LethalDamageEvent Becomes Equal to 1.00. Instead of modifying the DamageEventAmount here, modify LethalDamageHP to let the system know how much life to keep the unit alive with. Or you can just reference that LethalDamageHP value in order to know how much "overkill" damage was dealt.
  • To catch a unit as soon as the damage is applied against its Hit Points, use AfterDamageEvent Equal to 1.00.
  • Usage of the "<Event> becomes EQUAL to <value>" can be extrapolated as per the below:
    • EQUAL works as it always has - will run for any damage.
    • NOT EQUAL only runs for code damage.
    • LESS THAN only runs for damage from attacks but not coded attacks.
    • LESS THAN OR EQUAL only runs for melee attacks but not coded attacks.
    • GREATER THAN OR EQUAL only runs for ranged attacks but not coded attacks.
    • GREATER THAN only runs for Spell damage but not coded spell damage.

  • Damage Engine 5 and higher requires the latest Warcraft 3 patch (currently 1.32).
  • For people who did not update their game to Reforged / have not updated to Reforged yet. Alternatively, adding the below JASS script to the top of the DamageEngine library SHOULD enable it to work too:

    function BlzGetEventIsAttack takes nothing returns boolean
         return BlzGetEventDamageType() == DAMAGE_TYPE_NORMAL
  • I have created a Pastebin for all information pertaining to Damage Engine 3.8, including the link to download it, via: Damage Engine | HIVE.
  • As of 20 June 2020, JNGP users who are still on WarCraft 3 1.26 can benefit from Damage Engine 3A, which integrates many of the design choices added in various stages of Damage Engine 5. This is a special update which only requires the JASS script be replaced (no new GUI variables added). Can be found here: Damage Engine 3A.0.0.0 and | HIVE

Unit attacks or casts a spell. The pure damage is assessed at this point - damage dice, evasion, critical strike. There is currently no event to affect or modify these at source.
→ →
The projectile or weapon hits the target unit
→ →
EVENT_UNIT_DAMAGING is fired before any modifications to the damage are made.
→ ↓
↓ ←
User changes to DamageEventAmount and/or to DamageEventDamageT/AttackT/WeaponT are saved into the WC3 engine.
← ←
If any recursive damage is detected from any of those events, it is postponed and the current damage will continue first.
← ←
Damage Engine deploys the PreDamageEvent
WarCraft 3 processes the user damage.
→ →
WarCraft 3 then distributes the user damage into Spirit Link (before armor)
→ →
WarCraft 3 runs any interrupting events, such as spirit link or defensive damage like Thorns Aura
→ ↓
↓ ←
The EVENT_UNIT_DAMAGED event runs. This is the original event we have always had access to. Damage Engine will either keep using the original variables from the DAMAGING event, or if there was Spirit Link/defensive damage it will freshly retrieve the event values from WC3 and only retain DamageEventPrevAmt.
← ←
Once any potential recursive WarCraft 3 damage is processed, the armor/mana shield modifications to the damage are performed.
← ←
If such events such as Spirit Link were detected, they fire their own EVENT_UNIT_DAMAGING & EVENT_UNIT_DAMAGED, and DamageEngine processes it along the way for the user.
If the damage is above zero, ArmorDamageEvent will run. If any recursive damage is detected, it is postponed.
→ →
The user can make modification to the damage here with the after-damage amount.
→ →
The user can access DamageEventPrevAmount if they want to know the damage amount before user changes/WarCraft 3 changes.
→ ↓
↓ ←
The user can specify whether or not to change LethalDamageHP in order to stop the unit from dying.
← ←
If the damage is still above zero, check if the damage is lethal. If so, run LethalDamageEvent 1.00. If any recursive damage is detected, it is postponed.
← ←
If the user wants the value that DamageEngine used to have with DamageEventPrevAmt (after WarCraft 3 processing but before user changes) they multiply DamageEventPrevAmt x DamageScalingWC3.
Once all modification is done, run OnDamageEvent. If any recursive damage is detected, it is postponed.
→ →
After a new damage instance is detected, or the 0.00 timer expires, run AfterDamageEvent. If any recursive damage is detected, it is postponed.
→ →
Run all potential recursive Unit - Damage Target function calls in chronological order (first in, first out).

How to install Damage Engine:
  1. Use WarCraft 3 Version 1.32
  2. If you're upgrading from 3.8 or prior, please delete the entire "Damage Engine" category from your map.
  3. Copy & Paste the Damage Engine category from the attached map to your own map.
How do I upgrade to the latest Damage Engine?
- Depending on the complexity, you'll either need to re-copy the Damage Engine category or just the Damage Engine script. Generally, you can use this as a guide:

  • Damage Engine _._._.x - only requires copying of the JASS script
  • Damage Engine _._.x._ - generally only needs copying of the JASS script, but read the patch notes in case there are changes you may want to make to your own code in order to utilize the changes.
  • Damage Engine _.x._._ - delete your current Damage Engine category or manually add the missing variables to your Variable Editor, and update your JASS script.
  • Damage Engine x._._._ - this occurs very infrequently. Typically requires changes to the way Damage Engine needs to be installed and used.

Notes about upgrading from Damage Engine 4.0 or prior:
  • Revert any custom Object Editor changes made (such as Life Drain reversal, Spell Damage Reduction inversion, etc).
  • You can safely delete the custom spells "Spell Damage Detection" and "Cheat Death Ability"
  • You can delete the Unit Indexer trigger if you do not use it or would prefer to use a different indexer.
  • You should delete any "Mana Shield fix" or "Finger of Death fix" you may have imported, as well as revert any Object Editor data that was required to make it work, as these are no longer needed.
  • !!!DEPRECATED FEATURE!!! As of 5.4, do not bother to take any recursive damage mitigation - Damage Engine will now handle all of that for you!
  • !!!DEPRECATED FEATURE!!! Do not use "ClearDamageEvent" - it does nothing. Just delete it.
  • !!!DEPRECATED FEATURE!!! Do not use "NextDamageOverride" - set NextDamageType = DamageTypePure instead.
  • !!!CHANGED FEATURE!!! If the system detects code damage and the user did not specify it as any particular DamageEvenType, the system will assign it DamageTypeCode automatically.
  • !!!CHANGED FEATURE!!! DamageModifierEvent 1.00-3.00 now run prior to armor reduction. This enables the user to modify the damage before armor and resistance changes are applied - also before Mana Shield and Anti-Magic shell kick in, so no more need for special triggers.

  • Q: How can I detect when a unit gets damaged?
  • A: Create a trigger with the event: "Game - Value of Real Variable <DamageEvent> becomes Equal to 1.00".
    • Use the following custom variables to reference the event responses:
      • DamageEventSource - the unit dealing the damage
      • DamageEventTarget - the unit getting damaged
      • DamageEventAmount - how much damage is being dealt
      • DamageEventAttackT - which attack type was used by DamageEventSource to damage DamageEventTarget
      • DamageEventDamageT - which damage type was used to damage the target (ie. UNIVERSAL for ultimate damage, or NORMAL for damage that gets reduced by armor).
      • DamageEventDefenseT - which defense type does the target unit have (ie. Hero, Fortified, Unarmored).
      • DamageEventArmorT - which armor type does the target unit have (ie. Flesh, Ethereal, Stone).
      • DamageEventPrevAmt - what the value of the damage was before being modified by armor, ethereal/item bonuses or user changes.
  • Q: How do I modify the damage that is dealt to a unit?
  • A: Create a trigger with the event: "Game - Value of Real Variable <PreDamageEvent> becomes Equal to <any value>".
    • You can change the following variables to affect the damage that will be dealt:
      • DamageEventAmount - how much damage will be dealt (before armor reductions)
      • DamageEventAttackT - which attack type will be used by DamageEventSource to damage DamageEventTarget
      • DamageEventDamageT - which damage type will be used to damage the target.
      • DamageEventDefenseT - which defense type should the target unit have during this attack.
      • DamageEventArmorT - which armor type should the target unit have during this attack.
      • DamageEventArmorPierced - how much armor value to ignore when dealing this damage (applies to DAMAGE_TYPE_NORMAL only, otherwise all armor is ignored).

  • Q: How do I deal Pure damage to a unit (bypassing armor/skipping user modification)?
  • A: Use the following actions:
    • Set NextDamageType = DamageTypePure
    • Unit - Cause Source to damage Target for Amount using attack type Spells and damage type Universal

  • Q: How do I protect against recursive damage?
  • A: Damage Engine 5.4 and above is completely recursion-proof, using vJass hooks to detect registered Damage Event triggers.

  • Q: I've been using <insert Damage system here>. Can I use those with Damage Engine?
  • A: Better - Damage Engine has integrated cross-compatibility with all other approved Damage systems and even the major ones from outside of Hiveworkhop.

  • Q: Can I cause an attack to 'Miss' its target?
  • A: Kind of. Ranged attacks will still explode on the target, and on-hit effects will still apply, but you can do the following:
    • Use the event "PreDamageEvent becomes Equal to 1.00"
    • Use the following actions:
      • Set DamageEventAmount = 0.00
      • Set DamageEventArmorT = ARMOR_TYPE_NONE
      • Set DamageEventWeaponT = WEAPON_TYPE_NONE
    • Setting the weapon type and armor type to none like the above will stop any on-hit sounds from playing. When the Peasant attacks in the demo map, this is the trick I'm using. Instead of saying "MISSED!" I have the Floating Text saying "FAIL!" because - again - it's not exactly a "miss".

Thank you to Blizzard for continuing to work on this amazing game to give us awesome new natives that have the best possible control over incoming damage. Damage Engine brings that power to GUI. Also, a very special thank you to @KILLCIDE for getting me motivated to start up the 5.0 project in the first place.

Thank you to the users of this system who have helped me mold this project into the stable, powerful form it is in today!

For versions 3.8 and prior:

Thank you @looking_for_help for finding the spell damage detection method used in Damage Engine 3 - it was the greatest find since the undefend bug.

Thanks to Jesus4Lyf and @Nestharus for building the inspiration that originally led me to create DamageEngine.

Thank you Wietlol and looking_for_help for challenging me on this project to integrate solutions to problems I had not been made aware of, such as the importance of an After-Damage Event.

Thanks to @Spellbound for several crucial bug reports.

Damage Engine Config

Damage Engine vJass

Damage Engine Lua


  • Damage Engine Config
    • Events
      • Map initialization
      • Game - DamageModifierEvent becomes Greater than 0.00
      • Game - LethalDamageEvent becomes Less than or equal to 0.00
      • Game - DamageEvent becomes Not equal to 0.00
      • Game - AfterDamageEvent becomes Less than 0.00
      • Game - AOEDamageEvent becomes Greater than or equal to 0.00
      • Game - SourceDamageEvent becomes Equal to 0.00
      • Game - PreDamageEvent becomes Equal to 0.00
      • Game - ArmorDamageEvent becomes Equal to 0.00
      • Game - ZeroDamageEvent becomes Equal to 0.00
    • Conditions
    • Actions
      • -------- You can add extra classifications here if you want to differentiate between your triggered damage --------
      • -------- Use DamageTypeExplosive (or any negative value damage type) if you want a unit killed by that damage to explode --------
      • -------- - --------
      • -------- The pre-defined type Code might be set by Damage Engine if Unit - Damage Target is detected and the user didn't define a type of their own. --------
      • -------- "Pure" is especially important because it overrides both the Damage Engine as well as WarCraft 3 damage modification. --------
      • -------- I therefore gave the user "Explosive Pure" in case one wants to combine the functionality of the two. --------
      • -------- - --------
      • Set VariableSet DamageTypePureExplosive = -2
      • Set VariableSet DamageTypeExplosive = -1
      • Set VariableSet DamageTypeCode = 1
      • Set VariableSet DamageTypePure = 2
      • -------- - --------
      • Set VariableSet DamageTypeHeal = 3
      • Set VariableSet DamageTypeBlocked = 4
      • Set VariableSet DamageTypeReduced = 5
      • -------- - --------
      • Set VariableSet DamageTypeCriticalStrike = 6
      • -------- - --------
      • Custom script: call DamageEngine_DebugStr()


Lua - Fixed to match adjustment made in vJass version
Lua - Fixed to match adjustment made in vJass version
Lua - Fixed to match adjustment made in vJass version
Lua - Added support for Lua Fast Triggers ([Lua] Ridiculously Fast Triggers). Fixed an issue where the AfterDamageEvent wasn't always timed the correct way like it was in the JASS verion.
Lua - Fixed encapsulation issue and recursion issue with DamageEngine_inception. Now hooks UnitDamageTarget.
Lua - Release based on Damage Engine - Added the following clearer event names to make things less confusing for new users:
  • PreDamageEvent - can be used in place of DamageModifierEvent pre-armor modification
  • ArmorDamageEvent - can be used in place of DamageModifierEvent post-armor modification
  • OnDamageEvent - can be used instead of a non-zero DamageEvent
  • ZeroDamageEvent - can be used instead of a zero damage DamageEvent
  • SourceDamageEvent - runs at the same time as AOEDamageEvent, but doesn't need to hit multiple units.
Added "DamageFilterRunChance" - odds for the trigger to BE run (works inversely to DamageFilterFailChance).
Shortened the Configuration trigger so that it focuses primarily on what the user can modify.
Organized all variables into categories to help users better understand what does what.
Installation or updating from a previous version will require re-copying the entire Damage Engine folder.
Updated the demo map's text tag production to include a new custom update for ArcingTextTag, thanks to @Ugabunda and @Kusanagi Kuro.
Side note - the Demo Map's triggers have been heavily cleaned up and will now no longer cause crashes when being imported into a new map. -
  • Added a new functionality to the AOEDamageEvent, which allows it to fire even when only one unit is hit, if the AOEDamageEvent is registered as "Not Equal" instead of "Equal to". This is useful in a very specific scenario where an AfterDamageEvent may not be able to be relied upon to properly deallocate data from a running instance that needs to be able to function when multiple units are hit, but also needs to not fail when only one unit is hit.
  • Added additional filters for GUI users to avoid using trigger conditions in even more scenarios:
    • DamageFilterSource/TargetI (has item)
    • DamageFilterSource/TargetA (has ability)
    • DamageFilterSource/TargetC (has a certain classification, like hero or Tauren)
    • DamageFilterFailChance - odds for the trigger to not be run (ideal for critical strike or evasion)
  • Provided a way for GUI to un-register a Damage Event by setting "RemoveDamageEvent" to true from within their trigger's actions.
  • Moved the CreateTimer/CreateTrigger/CreateGroup calls that had been included in the globals block down to the onInit block as per request of @Ricola3D
  • Minor performance improvements thanks to @BLOKKADE - Fixed an issue with armor penetration sometimes bugging out. - Fixed an issue with the eventFilter not retaining its value during an AOE event. Fixed an issue with eventFilter when USE_MELEE_RANGE was set to false. Both issues reported by @lolreported -
I have fixed several potential points of failure reported by multiple users that stopped Damage Engine from working for the rest of the game. In any case there should no longer be ANY SITUATION where Damage Engine just "stops working", even in ways I can't predict. The most likely issue was with DamageScalingWC3/User having possible 0-division errors.​
Fixed the "configured" issue reported by @lolreported where manual configuration didn't work unless the damage and attack type checks were initialized tto -1.​
In addition to these fixed bugs, I have added several more static ifs so that advanced users have more control over getting rid of features they might not care about.​ - Fixed the issue reported by @KitsuneTailsPrower wherein the DamageInterface extension wasn't working. This needed to be fixed both in the Damage Engine source as well as the DamageInterface plugin itself. - Fixed the issue reported by @Wazzz where the armor reduction wasn't taken into consideration. Actually there was a much bigger flaw that I had overlooked that was prompting this. - Improved the logic of the 0 damage event.

  • Usage of the "DamageEvent becomes EQUAL to 1.00" now can be extrapolated further than ever before:
    • EQUAL works as it always has.
    • NOT EQUAL only runs for code damage.
    • LESS THAN only runs for damage from attacks.
    • LESS THAN OR EQUAL only runs for melee attacks.
    • GREATER THAN OR EQUAL only runs for ranged attacks.
    • GREATER THAN only runs for Spell damage.
  • Fully adapted Damage Engine to work with every other major DDS
  • Rewrote the internal script to use vJass structs: Damage and DamageTrigger.
  • Changed some of the vJass API. You can find the API listed in the Damage Engine trigger. Notably:
    • I removed UnitDamageTargetEx. You can replace this with Damage.apply.
      • The reason for this change is because of cross-compatibility. Rising Dusk's IDDS uses a different set of parameters for this function, so I removed it from my library to allow this to work seamlessly.
    • TriggerRegisterDamageEvent -> TriggerRegisterDamageEngine
    • RegisterDamageEvent -> RegisterDamageEngine
      • The reason for the above two changes is, like for UnitDamageTargetEx, because Rising Dusk's IDDS uses them. I don't want to make the same mistake I did with Table's API and preferred to walk back my API choices before things got out of hand again.
  • Various performance tweaks, bug fixes and re-commenting of variables.
  • Recursive damage is now processed more intelligently and possibly be more performance-friendly.
  • Adapted the cross-compatibility libraries for Weep and LFH's systems to use textmacros to insert themselves into Damage Engine (this might have been in the 5.6 update, but these two updates were both tailored to achieve similar goals). - Fixed a bug with Damage modification and laid groundwork for a bunch of optional vJass compatibility addons. - Patchwork on Melee/Ranged detection, recursion tracking. Also added the ability to modify damage from a DamageEvent to make it easier on beginners. - Fixed an issue where the DamageEventType for recursive damage that used NextDamageType would always default to DamageTypeCode.
Rewrote a significant amount of the internal code so that struct and GUI syntax both work - and are synchronized with each other. vJass-exclusive users can disable the GUI synchronization if they don't use any GUI damage events in their maps.​
Four new variables must be added to your variable editor:​
  • boolean NextDamageIsAttack
  • boolean NextDamageIsMelee
  • boolean NextDamageIsRanged
  • integer NextDamageWeaponT
Struct syntax should not need too much introduction - Damage.index is the triggering event ID, and the syntax is Damage.index.amount/source/target/etc. To initialize a JASS damage event, use:​
function RegisterDamageEvent takes code c, string eventName, real value returns nothing
The string is simplified: "Modifier", "" (for simple DamageEvent), "After", "Lethal", "AOE"​
Finally, a neat QOL improvement is that I have assigned weight to each of the events. When registering an event, you can include numbers different than 1, 2, 3 or 4 (for modification) or just the plain "1" for the others. Now you can set your own sequencing and use 1.5, 3.14 or even -1 to give an even more extreme priority to something. Lower numbers run first, higher ones last.​ - Added support for the new native BlzGetEventIsAttack via "IsDamageAttack". Also updated the Config trigger to make importing a bit easier - Fixed a mis-flag of the IsDamageSpell value when not being actual spell damage. - Actually fixed the Cold Arrows issue (division by 0.00001 or something ...somehow... either way, it is fixed). - A fix which should hopefully quell the recent reports of damage events failing in complex situations involving Cold Arrows. - A ton of fixes to repair the issues plaguing Sunken City and anyone else who might be pushing this engine well beyond what I imagined it would be used for. Also added a couple of variables intended to be used to ricochet damage: CONVERTED_ATTACK_TYPE and CONVERTED_DAMAGE_TYPE. Check the demo map for how they can be used in a Unit - Damage Target action. - The "Inception" update. Advanced users can interact with Damage Engine via custom script to set DamageEvent_inception = true to allow their damage to potentially go recursive (to a fixed extent). - Hotfixed that modifiers 2 and 3 weren't running. - By using an innovative approach of hooking TriggerRegisterVariableEvent, I've permanently eliminated all risks of recursion in the engine. - Fixed unexpected behavior with DamageTypePure when it is affected by Anti-Magic Shell or Mana Shield. DamageTypePure now no longer ignores DamageScalingWC3. - Fixed an issue with AfterDamageEvent sometimes being delayed. Added DamageScalingUser to track the ratio of user modified damage, as well as DamageEventArmorPierced which allows the user to define how much armor to ignore when working with DAMAGE_TYPE_NORMAL. - Fixed an issue where with the final unit in a Spirit Link chain or the retaliating damage of Thorns/Carapace would not deploy an AfterDamageEvent. Also fixed an issue where AfterDamageEvent would still fire from DAMAGE_TYPE_UNKNOWN if it was greater than 0. Simply copy over the JASS from this post in order to update your own implementation.

  • Now features DamageEventArmorT and DamageEventDefenseT, which pull from the target unit's Object Editor data in order to allow you more complete access to detect and even MODIFY those defenses. Changes must be made in a DamageModifierEvent, and they are reverted as soon as armor is calculated.
  • Re-introduced AfterDamageEvent, which is the moment after the unit's life is changed, but before any recursive damage has run. - Bug fixes and performance improvements. No, really. Fixed an issue with the DAMAGED event running even though it was turned off (who would've guessed that?) - Engine re-tooling to improve accuracy and get Spirit Link/Defensive damage out of hardcoded mode - it will now work even in circumstances I haven't tested for (in case those weren't the only issues). Also fixed the Is Unit Moving resource. - Fixed an issue with Spiked Carapace and Thorns Aura where the melee attacker would not get recorded correctly. This required the same fix as I needed to apply for the initial target in a spirit link chain. - Tweaked recursion and fixed a few bugs. Re-introduced the zero damage event now that patch 1.31.1 brought it back. - Minor tweak to Spirit Link in rare situation. - Fixed issues related to Spirit Link. Now works intuitively as expected. - Crazy improvements - check out the details in "How to upgrade from Damage Engine 4.0 or earlier" and "How to use Damage Engine 5.1" - Oh man. Where do I even start?
  • You can now set/compare DamageEventDamageT, DamageEventAttackT or DamageEventWeaponT
  • No longer needs Unit Indexer nor any custom Object Editor data nor modifications.
  • Requires WarCraft 3 1.31 or higher.
  • Changed vanilla JASS code to vJass to clean up a lot of things such as making certain variables private.
  • Look for more details in "How to upgrade from Damage Engine 4.0 or earlier" - Never officially released, but was the first iteration which used SetEventDamage.
For and prior, see: Damage Engine | HIVE



Keywords:unit indexer, damage detection, damage event, weep, nestharus, looking_for_help, EVENT_PLAYER_UNIT_DAMAGED, damage engine, spell, physical, EVENT_PLAYER_UNIT_DAMAGED, attacktype, damagetype, weapontype, armortype, defensetype, BlzSetEventDamage

Damage Engine (Map)

Lua Damage Engine (Map)

23:20, 11th Jan 2015, BPower Criticism: On the one hand Damage Engine offers extremely high utility to every spell, system and map maker independent of the coding style ( GUI, JASS, vJass, .... ) on the other hand it's very easy to import and...




23:20, 11th Jan 2015, BPower


On the one hand Damage Engine offers extremely high utility to every spell, system and map maker
independent of the coding style ( GUI, JASS, vJass, .... ) on the other hand it's very easy to import and use.

Overall very read-able and well documentated code.
Also the demo map is good enough to help users to quickly learn the API provided by Damage Engine.

I don't want to diminish the finished performance of established damage detection systems
by other authors namely Nestharus ( DDS ), Cokemonkey ( StructuredDD ) and looking_for_help ( PDD ).
Quite the opposite is the case, these sometimes can fit better to what a user expects from a damage system.

Still I want to recommend Damage Engine in the first place for every user, looking for a damage detection system.

After having a chat with IcemanBo and PurgeandFire we decided to give Damage Engine a moderator rating of 6/5

Director's Cut


Code Reviewer
Level 26
Mar 19, 2008
Bribe.. now I'm mad on you..

I would make use of it in my project for hero contest, since I already made use of IsUnitMoving and Unit Indexer (you would take credits for all the systems =)). GDD is fine too, it uses same feature: Event - Value of Real variable and was here for years. Some things get old, new ones must replace them, like your's table did with Vexorian's one.
Great additional to unit indexer, allowing user to stick with one model of system and still gives efficient way to detect damage event.

Outstanding work done for GUI section. Deserves dc considering other GUI friendly systems related by you.
Why? because Unit - Takes Damage is a SPECIFIC UNIT EVENT, meaning you will need to register all possible units on the map... And it can cause leaks once the units die since the event stays...

That is where DDS comes in, they automate the registration for you, so that you can have a generic damage event (in this system for example, your generic damage event will be Game - DamageEvent becomes Equal to 1.00)... And they also avoid the leaks via several methods... (like in this case, once 15 units are removed from the detection list, they recreate the trigger to clear the events that are not needed anymore)
Level 4
Jul 17, 2011
Why? because Unit - Takes Damage is a SPECIFIC UNIT EVENT, meaning you will need to register all possible units on the map... And it can cause leaks once the units die since the event stays...

That is where DDS comes in, they automate the registration for you, so that you can have a generic damage event (in this system for example, your generic damage event will be Game - DamageEvent becomes Equal to 1.00)... And they also avoid the leaks via several methods... (like in this case, once 15 units are removed from the detection list, they recreate the trigger to clear the events that are not needed anymore)

oh finally, that made perfect sense, thanks dude! though, i was wondering if there's a system that can detect if the damage was dealt by an attack, or if it was dealt by a spell?

anyways, cool system, i think i'll use it :D



Code Moderator
Level 48
Sep 26, 2009
I'll have to check that out. By my preliminary checks I've seen that both Faerie Fire and Critical Strike could cause this event, so if these are still true in the latest patch then I should certainly seperate these out.

That's really weird and counter-intuitive that Faerie Fire and/or Critical Strike procure a 0 damage event.
First and Foremost, the event which works as a Damage detection is

"Game - UnitDamageEvent becomes Equal to 1.00" (which you should already know if you read the HOW TO USE part on the first post...)

the function "Game - UnitIndexEvent becomes Equal to 1.00" is used for the set-up and maintenance of this system...

First the system runs when a unit is indexed and deindexed by the UnitIndexer (which sets the UnitIndexEvent to 1 or 2)

Now the system checks if a damage event trigger is present, if not it creates one and registers some functions to it...

Next it will check if the unit is already registered within that trigger and if not, it registers the Unit gets damage event for that unit into the trigger (making that trigger run when the unit gets damaged)...

Now the function linked to this Damage event trigger is the one which causes the variable UnitDamageEvent to be equal to 1.00 and then sets the variables thus enabling you to catch the damage event by using the Event,

"Game - UnitDamageEvent becomes Equal to 1.00"

This system also recreates the damage event trigger every 15 deindexed units to remove already useless damage events (since there is no function for deregistering events)...




I don't understand these damage systems. Or the indexing.

Can't you just take the "when a unit is attacked" and then use floating text to display the damage? Or is this about controlling the damage?



Code Moderator
Level 48
Sep 26, 2009
"Unit is attacked" does not include "unit is attacked by spell/by triggers". You also can't get the damage from that event.

"Unit is attacked" is also an abusable event because it doesn't fire the instant the projectile leaves the unit or when the sword strikes its target, it fires the instant the unit's animation starts playing, so it is unreliable and abusable by spamming the "stop" button.

"Unit is damaged" fires when the sword connects with its target or when the missile hits its mark. It is the only way to get the amount of damage.

This system is necessary because there is no "any unit takes damage" event.


Code Moderator
Level 48
Sep 26, 2009
Updated Damage Event to become GUI Damage Engine. This now includes special damage types so you can customize your own in-game damage.

If you trigger all spell damage in the game, you can take advantage of this to distinguish between physical damage and actual attacks.

I will remove the Damage Modifier spell as this one seamlessly integrates all of its features.

Users of Damage Modifier do not need to change their codes, just to delete the DamageModifer script and replace the existing Damage Event with Damage Engine.
Read this?

Bribe said:
Damage Engine lets you detect, amplify, block or nullify damage, and lets you cause special or undetectable damage. Just reference DamageEventAmount/Source/Target, to get the necessary damage event data.

Detect damage: use the event "DamageEvent Equal to 1.00"
Detect zero-damage: use the event "DamageEvent Equal to 2.00"
To change damage before it's dealt: use the event "DamageModifierEvent Equal to 1.00"

Modify DamageEventAmount/ExplodesUnit/Override from a "DamageModifierEvent Equal to 1.00" trigger. To prevent your script's damage stacking with others, include the condition "DamageEventOverride Equal to false".

Likewise, set "DamageEventOverride" to true if you don't want other scripts to stack with it.

If you need to reference the original in-game damage, use the variable "DamageEventPrevAmt".

If you trigger all non-attack damage in the game, you can tell the difference between in-game damage and triggered damage, and you can customize the type of triggered damage as well. You set the variable "DamageEventType" accordingly, <before> triggering the damage.

DamageEventType will be 0 if the damage was dealt in-game or if you didn't set it right before causing the damage. You can create your own special damage types and add them to the list, and/or you can reference the existing ones (DamageTypeSpell/DOT/Ranged).




I know about the abuse from the attacks. Maybe not as abusing with the stop button, since you have to click stop each time the unit's attack animation fires which is pretty insane and for what point?

But the abuse in my thought comes out during special attack modifiers (Crit, Bash, Evasion) because using the triggers "Unit is attacked" and putting something like "Deal X damage to attacked unit" doesn't check if the attack missed or if your attack bashed the target. I think that is more abuse-able.

Still, does the system gives control over that?
Of course... since missed attacks don't register damage...

also using unit is attacked for ranged attacks is super bad you know? since it will do the actions even if the missile just started to fly...

and also, using this system, you can do a lot of things like doing a certain action if the damage taken is equal to a certain amount, which is totally impossible with Unit is Attacked...

sentrywiz said:
Can't you just take the "when a unit is attacked" and then use floating text to display the damage? Or is this about controlling the damage?

Unit is attacked don't register damage (since it happens at the start of the attack) so the method ur proposing won't work... if you do this, the damage text will always be 0
Level 11
Mar 18, 2009
So the update allows you to see the damage type as well as "trigger" and "original" damage meaning it can tell the difference between 14¤ different types of damage? Sounds great to me :D

¤(Spells, Magic, Normal, Pierce, Chaos, Siege and Hero *2)

Also, is it possible to add a function that can see if it comes from a area of effect source? (Thundercalp-ish type)?


Code Moderator
Level 48
Sep 26, 2009
There is no certain way to detect in-game bash or critical strike, you'd have to trigger those which is easy enough anyway (use DamageModifierEvent, set the variable DamageEventAmount to double, triple, quadruple etc/usw.)

The point to absusing "Unit is Attacked" is to quickly trigger a critical strike because then you can feign a lot of bonus damage in-game.

I'm not sure if I've answered your question or if I should elaborate more.

Well, anyone can explain how to disable it when cast spell? I need it only for normal damage, and please i dont understand it well, if anyone can explain slowly i would be happy.

Instead of having your spell damage done in object editor, you will need to have your spell damage done in triggers.

When you deal damage, do this:

  • Set DamageEventType = DamageTypeSpell
  • Unit - Cause blah blah blah...
Also, is it possible to add a function that can see if it comes from a area of effect source? (Thundercalp-ish type)?

You could create a fourth damage type called DamageTypeAOESpell, and if you trigger the damage you will be able to differentiate.


Code Reviewer
Level 26
Mar 19, 2008
^Yeah; thats what every intuitive DD is about.
Anyways, who has approved this? Bride, it was you? ^^
The reason why I'm asking, is fact that there is no mod comment, plus there isn't DC anywhere ;/ How sad.

..some cheating won't hurt anyone - Bribe go score DC for yourself, you are mod anyways ;>
Level 3
Nov 6, 2010
It's great but there is some problems with the system.

1-) It says that Archmage is healed when is attacked by a water elemental but it doesn't.
2-) It says that peasant deals 0 damage. It's not ok always. It can deal damage to Archmage (or heroes?).
3-) And there comes a bigger problem; When peasant hits footman or rifleman, they have massive hp (like 100.000 - i know it is for blocking damage) but their hp is not going down to normal.
4-) The 3rd problem happens when the unit is moving.

There is a replay in attachments shows the problems i said.

PS: I'm sorry for my English. English isn't my native language.


  • Damage Engine Some Bugs.w3g
    5.8 KB · Views: 385
Last edited:


Code Moderator
Level 48
Sep 26, 2009
I have been unable to reproduce these results on my earlier tests but
I will check out your replay as well.

+rep for the help getting this sorted. I apologize about this mixup.

This is the second time these results have been reported. I am not
sure why I am not experiencing the same things myself.

I have the day off tomorrow and my wife has to work, so I finally
get some time to look into this situation.

For now I recommend users to not use this system until I can get
it fixed tomorrow.


Code Moderator
Level 48
Sep 26, 2009
egenimo, I have fixed this problem after some grueling hours of search.

I place the blame on Blizzard for this one, the timer which removes the ability was (is) expiring twice. I have fixed it to compensate for this knowing that the timer will expire twice, however I have absolutely no idea why the timer is doing that in the first place.

Again, I blame Blizzard. There's no logical reason why it's not expiring just once.

This system is now, once again, safe to use. I apologize for the inconvenience!!!
Level 4
Jan 9, 2011
damage numbers show for units you can't see

Can you fix this because I can't have that in my map when a hero is fighting neutral creeps as this would give away position to enemy. A suggestion would be to hide the text if the unit is not visible.:vw_wtf:
Level 4
Jul 24, 2010
1. I really love your "End function" in GUI. LoL
2. I think convert this to jass will make this much easier to read. It is so hard to read in GUI.
3. Great for GUIers.
Problem 3 is easily fixed by increase "Giving HP Ability" from 500.000 to whatever higher.

I am busy today, will test this great system later.


Code Moderator
Level 48
Sep 26, 2009
I have fixed this to completely eliminate a couple of bugs.

1 is the one already explained, about the timer expiring twice. It only expires once now.

2 is rare but it's good that I've fixed it, so I recommend updating your maps to use this new update. It now removes the unit's bonus life ability before firing any new events, in case of recursion or something, so now you will get proper life/max life readings.


Code Moderator
Level 48
Sep 26, 2009
Update: Added support for Weep's GUI Damage Detection System (GDD). You only have to replace his system code with the following code to make it work:

//    real udg_GDD_Event = 0
//    real udg_GDD_Damage = 0
//    unit udg_GDD_DamagedUnit = null
//    unit udg_GDD_DamageSource = null

function GDD_Event takes nothing returns boolean
    local unit s = udg_GDD_DamageSource
    local unit t = udg_GDD_DamagedUnit
    local real v = udg_GDD_Damage
    set udg_GDD_DamageSource = udg_DamageEventSource
    set udg_GDD_DamagedUnit = udg_DamageEventTarget
    set udg_GDD_Damage = udg_DamageEventAmount
    set udg_GDD_Event = 1
    set udg_GDD_Event = 0
    set udg_GDD_DamageSource = s
    set udg_GDD_DamagedUnit = t
    set udg_GDD_Damage = v
    set s = null
    set t = null
    return false

function InitTrig_GUI_Friendly_Damage_Detection takes nothing returns nothing
    local trigger t = CreateTrigger()
    call TriggerRegisterVariableEvent(t, "udg_DamageEvent", EQUAL, 1)
    call TriggerRegisterVariableEvent(t, "udg_DamageEvent", EQUAL, 2)
    call TriggerAddCondition(t, Filter(function GDD_Event))
    set t = null