Damager

using UnityEngine;
using UniRx;

public class Damager : MonoBehaviour
{
    [SerializeField] private int _damage = 30;

    public int Damage
    {
        set => _damage = value;
    }

    public GameObject Owner { get; set; }

    public Subject<Health> OnGiveDamage = new Subject<Health>();
    public Subject<Health> OnFinalDamage = new Subject<Health>();

    private void OnTriggerEnter2D(Collider2D collision)
    {
        if (collision.TryGetComponent<Health>(out var health))
        {
            if (health.Owner.Equals(Owner)) return;

            OnGiveDamage.OnNext(health);

            var disposable = health.OnEmpty.Subscribe(OnFinalDamage);

            health.TakeDamage(_damage, gameObject);

            disposable.Dispose();
        }
    }
}