DOD

using UnityEngine;
using System.Collections.Generic;

public struct EnemyData
{
    public float health;
    public float speed;
}

public class EnemySpawner : MonoBehaviour
{
    public EnemyHandler enemyHandler;
    public GameObject enemyPrefab;

    void Spawn()
    {
        var go = Instantiate(enemyPrefab);
        enemyHandler.RegisterEnemy(go.transform, 100f, 3f);
    }
}

public class EnemyHandler : MonoBehaviour
{
    public Transform target;

    List<Transform> transforms = new();
    List<EnemyData> enemies = new();

    public void RegisterEnemy(Transform t, float health, float speed)
    {
        transforms.Add(t);
        enemies.Add(new EnemyData
        {
            health = health,
            speed = speed
        });
    }

    void Update()
    {
        Vector3 targetPos = target.position;

        for (int i = enemies.Count - 1; i >= 0; i--)
        {
            if (enemies[i].health <= 0f)
            {
                Destroy(transforms[i].gameObject);

                transforms.RemoveAt(i);
                enemies.RemoveAt(i);
                continue;
            }

            Vector3 dir = (targetPos - transforms[i].position).normalized;
            transforms[i].position += dir * enemies[i].speed * Time.deltaTime;
        }
    }

    public void Damage(int index, float dmg)
    {
        EnemyData e = enemies[index];
        e.health -= dmg;
        enemies[index] = e;
    }
}