private void addBtn_Click(object sender, RoutedEventArgs e)
        {
            string name = enemyNameTextBox.Text;
            int level = Convert.ToInt32(levelTextBox.Text);
            string role = roleComboBox.Text;

            if (!String.IsNullOrEmpty(name)
                && !String.IsNullOrEmpty(role)
                && (level > 0 && level <= 50))
            {
                Enemy enemy = new Enemy(name, level, role);

                if (IsDupeEnemy(enemy) == false)
                {
                    if (IsValidEnemy(enemy))
                    {
                        EnemyList.Add(enemy);
                        SaveEnemyList();
                    }
                    else
                    {
                        MessageBox.Show("Error creating enemy!");
                    }
                    
                }
                else
                {
                    MessageBox.Show("This enemy has already been added!");
                }                
            }
            else
            {
                MessageBox.Show("Invalid values! Unable to create enemy.");
            }

        }        
        private bool IsValidEnemy(Enemy enemy)
        {
            bool[] validEnemy = new bool[]
            {
                enemy.Stats.Health >= 0,
                enemy.Stats.Damage >= 0,
                enemy.Stats.Defense >= 0,
                enemy.ExperienceGranted >= 0,
                enemy.GoldGranted >= 0,
                enemy.Level > 0 && enemy.Level <= 50,
                !String.IsNullOrEmpty(enemy.Name),
                !String.IsNullOrEmpty(enemy.Role)                
            };


            return !validEnemy.Any(b => b == false);
        }
        private bool IsDupeEnemy(Enemy enemy)
        {
            var result = EnemyList.FirstOrDefault(e => e.Name == enemy.Name
                                                    && e.Level == enemy.Level
                                                    && e.Role == enemy.Role);

            return result != null;
        }