All about the Target

I wanted to review a very old thread which was posted almost one year ago but still isn't completely well documented anywhere:

"Target" is one bitch of a key.

And yet, it's arguably the most important KV to understand, as its found in almost every datadriven Action.

Having a wrong "Target" block is the number one reason of having to relaunch the game, testing with many combinations until you finally get the right context.

Quoting the wiki on this:

Note: These names mean different things in different events. It may require some experimentation to discover exactly what in each case.

This thread intends to compile every Target-related decision.

To test everything and get results, I used some simple scrips to test which parameters are seen in each event context. The KV and Lua Scripts are found in the second post, which also contains all the debug data.

After running many tests with different ability behaviors, here's what I got:

ABILITY EVENT CONTEXTS

Behavior: DOTA_ABILITY_BEHAVIOR_NO_TARGET

Event	Target
OnSpellStart	CASTER, UNIT, ATTACKER
OnAbilityPhaseStart	CASTER, UNIT, ATTACKER

DOTA_ABILITY_BEHAVIOR_UNIT_TARGET

This behavior adds TARGET as a possible value for the Target key:

Event	Target
OnSpellStart	CASTER, TARGET, UNIT, ATTACKER
OnAbilityPhaseStart	CASTER, TARGET, UNIT, ATTACKER

AbilityChannelTime > 0

DOTA_ABILITY_BEHAVIOR_CHANNELLED only purpose is to change the ability Tooltip to "Channeled". In fact, the BEHAVIOR_CHANNELED isn't even needed, "AbilityChannelTime" is all that matters for the actual ability behavior.

Event	Target
OnChannelFinish	CASTER, TARGET, UNIT, ATTACKER
OnChannelInterrupted	CASTER, TARGET, UNIT, ATTACKER
OnChannelSucceeded	CASTER, TARGET, UNIT, ATTACKER

With Linear and Tracking Projectile Actions

Event	Target
OnProjectileFinish	CASTER, TARGET, PROJECTILE
OnProjectileHitUnit	CASTER, TARGET, PROJECTILE

DOTA_ABILITY_BEHAVIOR_TOGGLE

Event	Target
OnToggleOff	CASTER
OnToggleOn	CASTER

Item pickup and drop

Event	Target
OnEquip	CASTER
OnUnequip	CASTER

Any Behavior

Event	Target
OnOwnerDied	CASTER
OnOwnerSpawned	CASTER
OnUpgrade	CASTER

MODIFER EVENT CONTEXTS

Caster-Target

Target always refers to the owner of the modifier.

Event	Target
OnCreated	CASTER, TARGET
OnDestroy	CASTER, TARGET
OnIntervalThink	CASTER, TARGET
OnProjectileDodge	CASTER, TARGET

Damage

In these events we can send an extra parameter, referenced as %attack_damage

Note that this is not a value taken from an AbilitySpecial, instead it is generated by the system to be used in very particular events.

Event	Target	%attack_damage value
OnTakeDamage	CASTER, UNIT, ATTACKER	post reduction
OnDealDamage	CASTER, UNIT, ATTACKER	post reduction

Attacks

In some of the attack events we can also use the %attack_damage

Event	Target	%attack_damage value
OnAttack	CASTER, TARGET, ATTACKER	0
OnAttackStart	CASTER, TARGET, ATTACKER	0
OnAttackAllied	CASTER, TARGET, ATTACKER	0
OnAttacked	CASTER, TARGET, ATTACKER	post reduction
OnAttackLanded	CASTER, TARGET, ATTACKER	before reduction, the real attack value
OnAttackFailed	CASTER, TARGET, ATTACKER	before reduction, the real attack value

Killing

Event	Target
OnDeath	CASTER, UNIT, ATTACKER
OnKill	CASTER, UNIT, ATTACKER
OnHeroKilled	CASTER, TARGET, ATTACKER

Caster-Unit

Event	Target	Extra
OnAbilityEndChannel	CASTER, UNIT	TARGET if the ability isn't NO_TARGET
OnAbilityExecuted	CASTER, UNIT	TARGET if the ability isn't NO_TARGET
OnOrder	CASTER, UNIT	TARGET if the Order is an ability with target
OnRespawn	CASTER, UNIT	needs "Attributes" "PERMANENT" on its modifier
OnManaGained	CASTER, UNIT
OnSpentMana	CASTER, UNIT
OnStateChanged	CASTER, UNIT
OnTeleporting	CASTER, UNIT
OnTeleported	CASTER, UNIT
OnUnitMoved	CASTER, UNIT
OnHealReceived	CASTER, UNIT
OnHealthGained	CASTER, UNIT

Never Triggered

OnAbilityStart - Broken?

Please report if you find any inconsistencies.

On the next post you'll find the random rambling analyzed to get the results.

Then we'll move to Multiple Targets, acting over different entities, Flags, etc.