衝突位置にエフェクトを発生させる【Unity】

Monster.cs

using UnityEngine;
using System.Collections;

public class Monster : MonoBehaviour
{

  //エフェクトのプレハブへのパス
  private const string EFFECT_PATH = "Effect/Collision";

  void OnCollisionEnter2D (Collision2D collider)
  {
    //衝突エフェクト
    foreach (ContactPoint2D point in collider.contacts) {
      GameObject effect = Instantiate (Resources.Load (EFFECT_PATH)) as GameObject;
      effect.transform.position = (Vector3)point.point;
    }

  }

}