MayHeCome/Assets/Shader/maskShader.shader

Shader "Custom/LayerMaskShader"
{
    SubShader
    {
        Tags { "Queue" = "Overlay" }
        Pass
        {
            ZWrite Off
            ColorMask 0
            Stencil
            {
                Ref 1
                Comp always
                Pass replace
            }
        }
    }
}