ObjectSpawner

   [CanEditMultipleObjects]
   public class ObjectSpawner : MonoBehaviour
   {
       [SerializeField] private GameObject[] objects;
       [Space]
       [SerializeField] private Color gizmoColor = new Color(193, 96, 36, 185);

       private float averangeSize;

       private void Awake()
       {
           Instantiate(objects[Random.Range(0, objects.Length - 1)], transform);
           CalculateAverageSize();
       }

       private void OnDrawGizmos()
       {
           if (objects != null && objects.Length > 0) CalculateAverageSize();

           DrawGizmo();
       }

       private void OnDrawGizmosSelected()
       {
           if (objects != null && objects.Length > 0)  DrawGizmo();
       }

       private void DrawGizmo()
       {
           float averageHeight = CalculateAverageSizeY();
           Vector3 gizmoPositionLocal = new Vector3(0, averageHeight / 2, 0);

           Gizmos.matrix = transform.localToWorldMatrix;

           Gizmos.color = gizmoColor;
           Gizmos.DrawCube(gizmoPositionLocal, DrawAverageSizeGizmo());
           Gizmos.color = gizmoColor * 2;
           Gizmos.DrawWireCube(gizmoPositionLocal, DrawAverageSizeGizmo());
       }

       public float CalculateAverageSize()
       {
           float volumeSum = 0f;
           foreach (GameObject obj in objects)
           {
               Vector3 objSize = obj.transform.lossyScale;
               float objVolume = objSize.x * objSize.y * objSize.z;
               volumeSum += objVolume;
           }
           averangeSize = volumeSum / objects.Length;
           return averangeSize;
       }

       public Vector3 DrawAverageSizeGizmo()
       {
           float averageSizeX = CalculateAverageSizeX();
           float averageSizeY = CalculateAverageSizeY();
           float averageSizeZ = CalculateAverageSizeZ();

           // Create a new Vector3 with the average size as the length of the vector
           return new Vector3(averageSizeX, averageSizeY, averageSizeZ);
       }

       private float CalculateAverageSizeX()
       {
           float sum = 0f;
           foreach (GameObject obj in objects)
           {
               Bounds bounds = obj.GetComponent<Renderer>().bounds;
               sum += bounds.extents.x * 2; // Get the width of the bounding box
           }
           return sum / objects.Length;
       }

       private float CalculateAverageSizeY()
       {
           float sum = 0f;
           foreach (GameObject obj in objects)
           {
               Bounds bounds = obj.GetComponent<Renderer>().bounds;
               sum += bounds.extents.y * 2; // Get the height of the bounding box
           }
           return sum / objects.Length;
       }

       private float CalculateAverageSizeZ()
       {
           float sum = 0f;
           foreach (GameObject obj in objects)
           {
               Bounds bounds = obj.GetComponent<Renderer>().bounds;
               sum += bounds.extents.z * 2; // Get the depth of the bounding box
           }
           return sum / objects.Length;
       }
   }