Tags and Requirements¶

Tags are the connective tissue of GAS. Gameplay Effects use tags in several distinct ways: to identify themselves, to grant tags to targets, to conditionally apply, to inhibit, and to trigger removal. Each of these roles is handled by a different GE Component, and understanding which component does what is key to configuring effects correctly.

Tag Roles at a Glance¶

Asset Tags¶

Configured via UAssetTagsGameplayEffectComponent.

Asset tags describe what the effect is, not what it does to the target. They are metadata on the GE asset itself. The target actor doesn't gain these tags — they live on the effect.

Uses:

• Immunity matching: "Block all effects tagged Damage.Fire"
• Querying active effects: "Does the target have any active effect tagged Buff?"
• Removal matching: "Remove all active effects tagged Debuff.Poison"

Inheritance: Asset tags use FInheritedTagContainer, which supports tag inheritance from parent GE Blueprints. If a parent GE has Damage, a child GE automatically has Damage too (unless it explicitly removes it).

Parent GE Asset Tags: Damage, Damage.Physical
Child GE (inherits): Damage, Damage.Physical, Damage.Physical.Bleed  ← added by child

Granted Tags (Target Tags)¶

Configured via UTargetTagsGameplayEffectComponent.

These tags are applied to the target actor while the GE is active. When the GE is removed, the tags are removed. If the GE is inhibited, the tags are also removed (and re-added when uninhibited).

Uses:

• Marking states: State.Stunned, State.OnFire, State.Invisible
• Enabling/disabling other systems: abilities that check State.CanAttack
• Triggering other effects' ongoing/removal requirements

Example: A freeze effect grants State.Frozen. Other effects can use this as an ongoing requirement — a "Shatter" bonus damage effect only works while the target has State.Frozen.

Blocked Ability Tags¶

Configured via UBlockAbilityTagsGameplayEffectComponent.

While the GE is active, abilities on the target that have any of the specified tags are prevented from activating. Already-active abilities are not cancelled (use UCancelAbilityTagsGameplayEffectComponent for that).

Example: A silence effect with blocked ability tags Ability.Magic prevents all magic abilities from being activated.

Application Tag Requirements¶

Configured via UTargetTagRequirementsGameplayEffectComponent (the ApplicationTagRequirements property).

These are pass/fail at application time. If the target's tags don't satisfy the requirements when the GE tries to apply, the application fails entirely — the GE is never added.

FGameplayTagRequirements has two containers:

• RequireTags — The target must have all of these tags
• IgnoreTags — The target must have none of these tags

ApplicationTagRequirements:
  RequireTags: State.Vulnerable
  IgnoreTags: State.Immune

Result: The GE only applies if the target has State.Vulnerable AND does NOT have State.Immune

Ongoing Tag Requirements¶

Also on UTargetTagRequirementsGameplayEffectComponent (the OngoingTagRequirements property).

These are checked continuously while the effect is active. If the requirements stop being met, the effect is inhibited (not removed). If they are met again, the effect uninhibits.

This is the mechanism behind inhibition.

Example: A "Berserker Rage" buff with ongoing requirement RequireTags: State.LowHealth. The buff is only active when the character is at low health. It automatically inhibits when they heal up and uninhibits when their health drops again.

Removal Tag Requirements¶

Also on UTargetTagRequirementsGameplayEffectComponent (the RemovalTagRequirements property).

If the target's tags come to satisfy these requirements, the effect is removed permanently (not just inhibited). Removal requirements are also checked at application time — if already satisfied, the GE won't apply.

Example: A regeneration buff with removal requirement RequireTags: State.Dead. If the character dies, the regen is removed.

Remove Other Effects¶

Configured via URemoveOtherGameplayEffectComponent.

When this GE is applied, it removes other active GEs that match the configured FGameplayEffectQuery queries. This runs on application (including restacking).

Example: A "Cleanse" spell that removes all active effects whose asset tags match Debuff. Or more precisely — the query matches against granted tags, asset tags, source tags, modifying attributes, or even specific GE classes.

Cancel Abilities¶

Configured via UCancelAbilityTagsGameplayEffectComponent.

Cancels abilities on the target that match (or don't match) specified tags. Supports two modes:

• OnApplication — Cancels once when the GE is applied
• OnExecution — Cancels on each periodic execution

Modifier-Level Tag Requirements¶

Separate from GE-level tag requirements, individual modifiers can have their own SourceTags and TargetTags requirements. These don't prevent the GE from applying — they just make individual modifiers conditional within an already-applied effect.

See Modifiers: Modifier Tag Requirements for details.

Migration Reference¶

If you are upgrading from pre-5.3 or reading older tutorials, here is the mapping from old monolithic properties to new components:

The engine handles this migration automatically when old assets are loaded. See GE Components: Migration for details.

Common Patterns¶

Mutually Exclusive Buffs¶

Want "Fire Shield" and "Ice Shield" to be mutually exclusive?

1. Give both GEs an asset tag of Buff.ElementalShield
2. Add a URemoveOtherGameplayEffectComponent to each with a query matching Buff.ElementalShield

Applying Fire Shield removes any active Ice Shield (and vice versa).

State-Dependent Abilities¶

Want abilities that only work in certain states?

1. Your state effects grant tags like State.Airborne, State.Grounded
2. Your abilities check those tags via their activation requirements (on the ability side)
3. Optionally, use UBlockAbilityTagsGameplayEffectComponent on CC effects to block ability categories

Layered CC¶

Want a stun to override a slow, but not vice versa?

1. Stun grants CC.Stun and CC.Any
2. Slow has ongoing requirement: IgnoreTags: CC.Stun — it inhibits when stunned
3. Both grant CC.Any so abilities can check for "any CC active"