Target.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Target : MonoBehaviour {

	private float RotateSpeed = 100f;
	private float Radian = 0f;
	private float HeadPoint = 1.2f;

	private SpriteRenderer AttentionSprite;
	private Enemy parentEnemy;

	public Sprite Attention;
	public Sprite UnAttention;

	// Use this for initialization
	void Start () {
		AttentionSprite = GetComponent<SpriteRenderer> ();
		AttentionSprite.sprite = UnAttention;

		parentEnemy = transform.parent.GetComponent<Enemy> ();
	}
	
	// Update is called once per frame
	void Update () {
		Radian += Time.deltaTime;
		transform.Rotate (Vector3.up * Time.deltaTime * RotateSpeed);
		transform.localPosition = Vector3.up * HeadPoint + Vector3.up * (Mathf.Sin(Radian) / 10f);
		print (Mathf.Sin (Radian));

		if (parentEnemy.isDrawingAttention) {
			AttentionSprite.sprite = Attention;
		} else {
			AttentionSprite.sprite = UnAttention;
		}
	}
}