unification of troops

using System;
using System.Collections.Generic;
using System.Threading;
using System.Linq;

namespace ConsoleApp2
{
    class Program
    {
        static void Main(string[] args)
        {
            List<Soldier> detachment1 = new List<Soldier>
            {
                new Soldier("Ара","Аегис","Бебравич"),
                new Soldier("Гук","Аганим","Бебравич"),
                new Soldier("Шейм","Башка","Бебравич"),
                new Soldier("Кринж","Веномансер","Бебравич"),
                new Soldier("Зумер","Боксер","Бебравич"),
            };
            List<Soldier> detachment2 = new List<Soldier>
            {
                new Soldier("Сюр","Бабайка","Бебравич"),
                new Soldier("Втф","Абобус","Бебравич"),
                new Soldier("Джул","Dungeon","Бебравич"),
                new Soldier("Феил","Van","Бебравич"),
                new Soldier("Челик","Брусчатка","Бебравич"),
            };
            Console.WriteLine("До распределения: ");
            ShowDetachements(detachment1, detachment2);
            var soldiers = detachment1.Where(soldier => soldier.Surname.StartsWith("Б")).Union(detachment2).ToList();
            detachment1.RemoveAll(soldier => soldier.Surname.StartsWith("Б"));
            detachment2 = soldiers;
            Console.WriteLine("\nПосле распределения: ");
            ShowDetachements(detachment1,detachment2);
        }

        public static void ShowDetachements(List<Soldier> detachement1, List<Soldier> detachement2)
        {
            Console.WriteLine("\nПервый отряд: ");

            foreach (var soldier in detachement1)
            {
                soldier.ShowInfo();
            }
            Console.WriteLine("\nВторой отряд: ");

            foreach (var soldier in detachement2)
            {
                soldier.ShowInfo();
            }
        }
    }

    class Soldier
    {
        public string Surname { get; private set; }

        private string _name;
        private string _patronimyc;

        public Soldier(string name, string surname, string patronimyc)
        {
            _name = name;
            Surname = surname;
            _patronimyc = patronimyc;
        }

        public void ShowInfo()
        {
            Console.WriteLine($"Имя: {_name} || Фамилия: {Surname} || Отчество: {_patronimyc}");
        }
    }
}