Extremely basic turn based combat.

Need to add multiple characters.
need a way to select a target.
need a team concept so you can't target friendlies.
need an ability system.
need Kenny art

Assets/Scripts/BattleMenu.cs

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+using System;
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.UI;
+
+public class BattleMenu : MonoBehaviour
+{
+    private class Player
+    {
+        public int Health;
+        public int Damage;
+
+        public Action UpdateHealth;
+    }
+
+    private Player _user;
+    private Player _enemy;
+    private EnemyAi _enemyLogic;
+    private readonly List<Action> _turnOrder = new List<Action>();
+    private int _currentTurnIndex = 0;
+    
+    public Button attackButton;
+    public Text userHealth;
+    public Text enemyHealth;
+    
+    private void Awake()
+    {
+        _user = new Player {Health = 10, Damage = 1, UpdateHealth = UpdateUserHealth};
+        _enemy = new Player {Health = 10, Damage = 1, UpdateHealth = UpdateEnemyHealth};
+        _enemyLogic = new EnemyAi();
+        _enemyLogic.AttackCallback += EnemyAttack;
+    }
+    
+    private void Start()
+    {
+        attackButton.onClick.AddListener(PlayerAttack);
+        
+        _turnOrder.Add(UserTakeTurn);
+        _turnOrder.Add(_enemyLogic.TakeTurn);
+
+        _turnOrder[_currentTurnIndex]();
+        
+        UpdateUserHealth();
+        UpdateEnemyHealth();
+    }
+
+    private void UpdateUserHealth()
+    {
+        userHealth.text = $"Health: {_user.Health}";
+    }
+
+    private void UpdateEnemyHealth()
+    {
+        enemyHealth.text = $"Health: {_enemy.Health}";
+    }
+    
+    private void FinishTurn()
+    {
+        _currentTurnIndex = ++_currentTurnIndex % _turnOrder.Count;
+        _turnOrder[_currentTurnIndex]();
+    }
+    
+    private void PlayerAttack()
+    {
+        Attack(_user, _enemy);
+        // TODO: disable hud
+        attackButton.interactable = false;
+        FinishTurn();
+    }
+
+    private void EnemyAttack()
+    {
+        Attack(_enemy, _user);
+        FinishTurn();
+    }
+
+    private void UserTakeTurn()
+    {
+        // TODO: enable hud.
+        attackButton.interactable = true;
+    }
+
+    private void Attack(Player attacker, Player victim)
+    {
+        victim.Health -= attacker.Damage;
+        victim.UpdateHealth();
+        if (victim.Health <= 0)
+        {
+            Debug.Log("The victim died!");
+        }
+    }
+}

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Assets/Scripts/EnemyAi.cs

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+using System;
+
+public class EnemyAi
+{
+    public Action AttackCallback;
+    
+    public void TakeTurn()
+    {
+        AttackCallback();
+    }
+}

Assets/Scripts/EnemyAi.cs.meta

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