> ## Documentation Index
> Fetch the complete documentation index at: https://docs.kinemation.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Modify Avatar Mask

> Add custom weapon, IK, or attachment transforms to an Avatar Mask.

export const menuPath_0 = "Tools > KINEMATION"

export const imageCaption_0 = "Modify Avatar Mask hierarchy, bone, and mask fields."

export const image_0 = 
  <img
    src="/images/unity-tools/modify-avatar-mask.png"
    alt="Modify Avatar Mask with root, bone to add, and upper body mask fields"
  />

## Modify Avatar Mask

Use Modify Avatar Mask to add a custom transform path to an existing Unity <code>AvatarMask</code>. Use it when a layer must include a weapon bone, IK target, attachment, or other transform outside the standard humanoid mask.

Open **{menuPath_0}**, then select **Animation > Modify Avatar Mask**.

<Frame caption={imageCaption_0}>
  {image_0}
</Frame>

## Fields

| Field               | Purpose                                                               |
| ------------------- | --------------------------------------------------------------------- |
| **Root**            | Optional hierarchy root. The stored path starts below this transform. |
| **Bone To Add**     | Transform that the mask should include.                               |
| **Upper Body Mask** | Existing <code>AvatarMask</code> modified by the operation.           |

## Add a transform

<Steps>
  <Step title="Assign the hierarchy root">
    Assign **Root** when the mask path should be relative to a specific skeleton or item root.
  </Step>

  <Step title="Select the transform">
    Drag the required transform into **Bone To Add**.
  </Step>

  <Step title="Select the mask">
    Drag the target <code>AvatarMask</code> into **Upper Body Mask**.
  </Step>

  <Step title="Modify the mask">
    Click **Add Bone**, then inspect the mask's transform list.
  </Step>
</Steps>

<Warning>
  The tool modifies the selected <code>AvatarMask</code> in place. It adds only the selected transform, not its children. Commit or duplicate a shared mask first.
</Warning>

If a path ending with the same bone name already exists, the tool leaves the mask unchanged.