[C#] TextRPG2

  using System;

  namespace TextRPG2
  {
    class Program
    {
      static void Main(string[] args)
      {
        Game game = new Game();
        while(true){
          game.Process();
        }
      }
    }
  }

  using System;
  using System.Collections.Generic;
  using System.Text;

  namespace TextRPG2
  {
    public enum PlayerType 
    {
      None = 0 ,
      Knight = 1,
      Archer = 2,
      Mage = 3
    }

    class Player : Creature
    {
      protected PlayerType type = PlayerType.None;

      protected Player(PlayerType type) : base(CreatureType.Player)
      {
        this.type = type;
      }

      public PlayerType GetPlayerType() { return type; }       
    }

    class Knight : Player
    {
      public Knight() : base(PlayerType.Knight)
      {
        SetInfo(100, 10);
      }
    }

    class Archer : Player
    {
      public Archer() : base(PlayerType.Archer)
      {
        SetInfo(75, 12);
      }
    }

    class Mage : Player
    {
      public Mage() : base(PlayerType.Mage)
      {
        SetInfo(50, 15);
      }
    }
  }

  using System;
  using System.Collections.Generic;
  using System.Text;

  namespace TextRPG2
  {
    public enum MonsterType
    {
      None = 0,
      Slime = 1,
      Orc = 2,
      Skeleton = 3
    }

    class Monster : Creature
    {
      protected MonsterType type = MonsterType.None;
  
      protected Monster(MonsterType type) : base(CreatureType.Monster)
      {
        this.type = type;
      }

      public MonsterType GetMonsterType() { return type; }
    }

    class Slime : Monster
    {
      public Slime() : base(MonsterType.Slime)
      {
        SetInfo(10, 10);
      }
    }

    class Orc : Monster
    {
      public Orc() : base(MonsterType.Orc)
      {
        SetInfo(20, 15);
      }
    }

    class Skeleton : Monster
    {
      public Skeleton() : base(MonsterType.Skeleton)
      {
        SetInfo(15, 20);
      }
    }
  }

  using System;
  using System.Collections.Generic;
  using System.Text;

  namespace TextRPG2
  {
    public enum CreatureType
    {
      None,
      Player = 1,
      Monster = 2,
    }

    class Creature
    {
      CreatureType type;

      protected Creature(CreatureType type)
      {
        this.type = type;
      }

      protected int hp = 0;
      protected int attack = 0;

      public void SetInfo(int hp, int attack)
      {
        this.hp = hp;
        this.attack = attack;
      }

      public int GetHp() { return hp; }
      public int GetAttack() { return attack; }
      public bool IsDead() { return hp <= 0; }

      public void OnDamaged(int damage)
      {
        hp -= damage;
        if (hp < 0)
          hp = 0;
      }
    }
  }

  using System;
  using System.Collections.Generic;
  using System.Text;

  namespace TextRPG2
  {
    public enum GameMode
    {
      None,
      Lobby,
      Town,
      Field
    }

    class Game
    {
      private GameMode mode = GameMode.Lobby;
      private Player player = null;
      private Monster monster = null;
      private Random rand = new Random();

      public void Process()
      {
        switch (mode)
        {
          case GameMode.Lobby:
            ProcessLobby();
            break;
          case GameMode.Town:
            ProcessTown();
            break;
          case GameMode.Field:
            ProcessField();
            break;
        }
      }

      public void ProcessLobby()
      {
        Console.WriteLine("Select Type");
        Console.WriteLine("[1] Knight");
        Console.WriteLine("[2] Archer");
        Console.WriteLine("[3] Mage");

        string input = Console.ReadLine();
        switch (input)
        {
          case "1":
            player = new Knight();
            mode = GameMode.Town;
            break;
          case "2":
            player = new Archer();
            mode = GameMode.Town;
            break;
          case "3":
            player = new Mage();
            mode = GameMode.Town;
            break;
        }
      }

      public void ProcessTown()
      {
        Console.WriteLine("You entered Town!");
        Console.WriteLine("[1] Go to Field");
        Console.WriteLine("[2] Go to Lobby");

        string input = Console.ReadLine();
        switch (input)
        {
          case "1":
            mode = GameMode.Field;
            break;
          case "2":
            mode = GameMode.Lobby;
            break;
        }
      }

      public void ProcessField()
      {
        Console.WriteLine("You entered Field!");
        Console.WriteLine("[1] Fight");
        Console.WriteLine("[2] Run away to town with a certain chance");

        CreateRandomMonster();

        string input = Console.ReadLine();
        switch (input)
        {
          case "1":
            ProcessFight();
            break;
          case "2":
            TryExcape();
            break;
        }
      }

      private void TryExcape()
      {
        int randValue = rand.Next(0, 101);
        if(randValue < 33)
        {
          mode = GameMode.Town;
        }
        else
        {
          ProcessFight();
        }
      }

      private void ProcessFight()
      {
        while (true)
        {
          int damage = player.GetAttack();
          monster.OnDamaged(damage);
          if (monster.IsDead())
          {
            Console.WriteLine("You Win! :)");
            Console.WriteLine($"Left HP : {player.GetHp()}");
            break;
          }

          damage = monster.GetAttack();
          player.OnDamaged(damage);
          if (player.IsDead())
          {
            Console.WriteLine("You Lose! :(");
            mode = GameMode.Lobby;
            break;
          }
        }
      }
 
      private void CreateRandomMonster()
      {
        int randValue = rand.Next(0, 3);
        switch (randValue)
        {
          case 0:
            monster = new Slime();
            Console.WriteLine("Slime is created!");
            break;
          case 1:
            monster = new Orc();
            Console.WriteLine("Orc is created!");
            break;
          case 2:
            monster = new Skeleton();
            Console.WriteLine("Skeleton is created!");
            break;
        }
      }
    }
  }

  class Player : Creature

  public enum PlayerType 

  protected PlayerType type = PlayerType.None;

  private GameMode mode = GameMode.Lobby;

  protected Player(PlayerType type) : base(CreatureType.Player)

  this.type = type;

  class Player : Creature
  {
    protected Player(PlayerType type) : base(CreatureType.Player)
    {
      this.type = type;
    }
  ...