public function down(array $migrationData, $fields = [])
    {
        $this->guardAction($migrationData['action']);

        $opposites = [
            'delete' => 'create',
            'create' => 'delete',
            'remove' => 'add',
            'add'    => 'remove'
        ];

        $method = $opposites[$migrationData['action']] . 'Factory';

        return $this->$method($migrationData, $fields);
    }