# Kill Shape Block reference

The Kill Shape Block defines a shape that destroys particles that collide with it. The Block destroys particles by setting their `alive` attribute to `false`.

If you change the **Behavior** property of the block, the Block changes to the following:

- A [Collision Shape Block](Block-CollisionShape.md) if you set **Behavior** to **Collision**.
- A [Trigger Shape Block](Block-TriggerShape.md) if you set **Behavior** to **None**.

## Block compatibility

You can add the Kill Shape Block to the following Contexts:

- [Initialize](Context-Initialize.md)
- [Update](Context-Update.md)

To add a Kill Shape Block to your graph, open the graph element menu as described in [Adding graph elements](VisualEffectGraphWindow.md#adding-graph-elements) then select **Collision** > **Kill Shape**.

## Block settings

| **Property** | **Type** | **Description** |
|-|-|-|
| **Shape** | Enum | Sets the shape for particles to collide with. For more information, refer to the [Shape dropdown](#shape-dropdown) section. |
| **Mode** | Enum | Specifies how particles interact with the collider. The options are:<ul><li><strong>Solid</strong>: Destroys particles when they enter the shape. If you set <strong>Shape</strong> to <strong>Plane</strong>, particles collide with the plane when they travel away from the normal of the plane.</li><li><strong>Inverted</strong>: Destroys particles when they leave the shape. If you set <strong>Shape</strong> to <strong>Plane</strong>, particles collide with the plane when they travel in the same direction as the normal of the plane.</li></ul> |
| **Radius Mode** | Enum | Sets the collision radius of the particles. The options are:<ul><li><strong>None</strong>: Sets the collision radius to zero.</li><li><strong>From Size</strong>: Sets the collision radius for each particle to its individual size.</li><li><strong>Custom</strong>: Sets the collision radius to the value of **Radius** in the [Block properties](#block-properties).</li></ul> |
| **Collision Attributes** | Enum | Specifies whether Unity stores data in the collision attributes of particles. The options are:<ul><li><strong>No Write</strong>: Doesn't write or store collision attributes.</li><li><strong>Write Punctual Contact only</strong>: Updates the collision attribute only when a specific, single-point collision occurs. This setting has no effect in a Kill Shape Block.</li><li><strong>Write Always</strong>: Updates the collision attribute every time a collision occurs.</li></ul> |

<a name="shape-dropdown"></a>
### Shape dropdown

| **Shape** | **Description** |
|-|-|
| **Sphere**| Sets the collision shape as a spherical volume. |
| **Oriented Box** | Sets the collision shape as a box volume. |
| **Cone**| Sets the collision shape as truncated cone volume.|
| **Plane** | Sets the collision shape as a flat plane with infinite length and width. |
| **Signed Distance Field** | Sets the collision shape as a signed distance field (SDF), so you can create precise complex collision with an existing asset. To generate a signed distance field asset, use the [SDF Bake Tool](sdf-bake-tool.md) or an external digital content creation (DCC) tool. |

## Block properties

| **Input** | **Type** | **Description**|
|-|-|-|
| **Sphere**| [Sphere](Type-Sphere.md) | Sets the sphere that particles collide with. This property is available only if you set **Shape** to **Sphere**. |
| **Box** | [OrientedBox](Type-OrientedBox.md) | Sets the box that particles collide with. This property is available only if you set **Shape** to **Box**. |
| **Cone**| [Cone](Type-Cone.md) | Sets the cone that particles collide with. This property is available only if you set **Shape** to **Cone**. |
| **Plane** | [Plane](Type-Plane.md) | Sets the plane that particles collide with. This property is available only if you set **Shape** to **Plane**. |
| **Distance Field**| Signed distance field | Sets the signed distance field (SDF) that particles collide with. This property is available only if you set **Shape** to **Signed Distance Field**. |
| **Field Transform** | [Transform](Type-Transform.md) | Sets the position, size, and rotation of the **Distance Field**. This property is available only if you set **Shape** to **Signed Distance Field**. |
| **Radius**| Float | Sets the collision radius of the particles. This property is available only if you set **Radius Mode** to **Custom**. |

## Inspector window properties

| **Property** | **Type** | **Description** |
|-|-|-|
| **Behavior** | Enum | Specifies how particles behave when they collide with the shape. The options are: <ul><li><strong>None</strong>: Changes the Block to a Trigger Shape Block, so particles don't bounce off the shape.</li><li><strong>Collision</strong>: Changes the Block to a [Collision Shape Block](Block-CollisionShape.md), so particles bounce off the shape.</li><li><strong>Kill</strong>: Destroys a particle when it collides with the shape. This is the default in a Kill Shape Block.</li></ul> |