private void Start()
{
GameState.Reset();
this._inputListener.OnHit += OnHit;
//choose the random preset index
int i = Random.Range(0, this._targetsPopsitions.Count);
//init players and enemies
PlayerController.Instance.Init(10, this._spawnPopsitions[i], 5);
EnemyController.Instance.Init(7, 20);
EnemyController.Instance.OnAllPlayersKilled += GameFailed;
InitTargetPosition(i);
//start the timer
this._timer = Instantiate(new GameObject()).AddComponent <Timer>();
_timer.InitTimer(60, OnTimeChanged, OnTimerFinish);
}