daniele-quero

    [SerializeField]
    private int _lives = 3;

daniele-quero

    public void Damage(int dmg)
    {
        _lives -= dmg;
        if (_lives < 0)
            GameObject.Destroy(this.gameObject);
    }

daniele-quero

        else if (collision.tag == "Player")
        {
            Player player = collision.GetComponent<Player>();
            if (player != null)
                player.Damage(1);
        }

daniele-quero

ComponentClass component = gameObjectVariable.GetComponent<ComponentClass>();

daniele-quero

IEnumerator MyRoutine(){

  //do something, maybe repeatedly
  yield return null;
}

daniele-quero

IEnumerator MyOtherRoutine(){

  //stuff to do
  yield return new WaitForSeconds(3f);
}

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StartCoroutine(MyRoutine());

daniele-quero

    [SerializeField]
    private float _rate = 5f;

    [SerializeField]
    private GameObject _enemyContainer, _enemyPrefab;

    private Vector3 _position = Vector3.zero;

daniele-quero

IEnumerator SpawnEnemy(float rate)
    {
        while (true)
        {
            Instantiate(_enemyPrefab, _position, Quaternion.identity)
                .transform.SetParent(_enemyContainer.transform);
            yield return new WaitForSeconds(rate);
        }
    }

daniele-quero

    void Start()
    {
        StartCoroutine(SpawnEnemy(_rate));
    }