Projectile.cs

using System;
using UnityEngine;

public class Projectile : MonoBehaviour
{
    [HideInInspector] public Vector3 direction;
    [SerializeField] private float speed = 1f;
    private BossLevelManager bossLevelManager;

    [HideInInspector] public Transform playerTransform;

    [SerializeField] private float lifetime = 5f;
    [SerializeField] private float playerDeathDelay = 1f;

    [HideInInspector] public static Vector3 targetPosAfterReverse;

    [SerializeField] private float damageToBoss = 1f;
    private bool isReturning = false;

    private void Start()
    {   
        bossLevelManager = FindObjectOfType<BossLevelManager>();

        playerTransform = GameObject.FindGameObjectWithTag("Player").transform;

        targetPosAfterReverse = transform.position;

        if(playerTransform == null)
        {
            return;
        }

        if (gameObject.tag == "PowerfulArrow")
        {
            transform.rotation = Quaternion.Euler(0f, 0f, 180f);
        }
        else 
        { 
            transform.rotation = Quaternion.Euler(0f, 0f, -135f);
        }

        SetDirection();
        Destroy(gameObject, lifetime);
    }

    private void Update()
    {
        // Move the projectile in its forward direction
        if (playerTransform == null)
            return;

        if(isReturning)
        {
            transform.position += direction * speed * playerTransform.gameObject.GetComponent<BossKillerPlayerScript>().hitForce * Time.deltaTime;
        }
        else
        {
            transform.position += direction * speed * Time.deltaTime;
        }
    }

    private void OnTriggerEnter2D(Collider2D other)
    {
        if (other.CompareTag("Player"))
        {
            // Deal damage to player
            Destroy(other.gameObject, playerDeathDelay);
            UIManager.Instance.PopUpAnim(bossLevelManager.losePanel, Vector3.one);
            VFXManager.Instance.PlayEffect(VFXManager.Instance.bloodEffect, other.transform.position);
            SoundManager.PlaySound(SoundType.HIT);
            SoundManager.PlaySound(SoundType.LOSE);
            Destroy(gameObject, 0.1f);
        }
        else if(other.CompareTag("Bat"))
        {
            if (gameObject.tag == "PowerfulArrow")
                return;

            direction = (targetPosAfterReverse - other.transform.position).normalized;
            transform.rotation = Quaternion.Euler(transform.rotation.x, transform.rotation.y, 45f); // Rotate an arrow
            Debug.Log("Player hit the ball");
            isReturning = true;
        }
        
        if(other.CompareTag("Boss"))
        {
            if(isReturning)
            {
                other.GetComponent<Boss>().TakeDamage(damageToBoss);
                Debug.Log("Boss hit");
                Destroy(gameObject);
                isReturning = false;
            }
            
        }
    }

    protected virtual void SetDirection()
    {
        direction = (playerTransform.position - transform.position).normalized;
    }
}