private function _newRound()
	{
		/** @var RoundBasedEnvironmentFactory $environment_factory */
		$environment_factory = EnvironmentFactory::Get();

		if( !in_array(RoundBasedEnvironmentFactory::class, class_parents($environment_factory)) )
		{
			throw RuntimeException::EnvironmentFactoryIsNotRoundBased();
		}

		return $environment_factory->newRound($this->_currentRoundNo);
	}