private void Submit_ButtonClick(object sender, RoutedEventArgs e)
        {
            bool isNumeric = int.TryParse(tbHealthField.Text, out int health);

            if (String.IsNullOrWhiteSpace(tbNameField.Text) || String.IsNullOrWhiteSpace(tbHealthField.Text) || !isNumeric)
            {
                tb_SubmitErrorMessage.Text = "Please make sure that all entered values are valid";
            }
            else
            {
                string           name = tbNameField.Text;
                DamageType       type = (DamageType)cbTypeList_window.SelectedItem;
                int              targetId;
                CharacterAccount target;
                if (cbTargetType.SelectedIndex == 0)
                {
                    targetId = GameContainer.AddEnvironmentTarget(name, health, type);
                    target   = GameContainer.ActiveGame.AllTargets[targetId];
                    MainWindow.EnvironmentTargets.Add(target);
                }
                else
                {
                    targetId = GameContainer.AddVillainTarget(name, health, type);
                    target   = GameContainer.ActiveGame.AllTargets[targetId];
                    MainWindow.VillainTargets.Add(target);
                }

                MainWindow.AllTargets.Add(target);
                MainWindow.NonHeroTargets.Add(target);
                if (MainWindow.NonHeroTargets.Count == 1)
                {
                    MainWindow.lbNonHeroTargets.SelectedIndex = 0;
                }
                this.Close();
            }
        }