Some issues with enemy health goes below 0 fixed.

src/Archer.java

@@ -12,13 +12,13 @@ public Archer(String nickname) {
 
     public boolean attack(Enemy enemy){
         if (this.leftArrow == 0) {
-            enemy.HP--;
+            enemy.takeDamage(1);
             System.out.println("You have 0 arrows left so you grabbed your knife.\n" +
                     "You hit enemy 1 damage, Enemy HP left is: " + enemy.HP);
         }
         if (this.leftArrow > 0) {
             this.leftArrow--;
-            enemy.HP -= this.damage;
+            enemy.takeDamage(this.damage);
             System.out.println("You have " + this.leftArrow + " arrows left.");
             System.out.println("You hit enemy " + this.damage + " damage," +
                     " Enemy HP left is:" + enemy.HP);
@@ -54,9 +54,9 @@ public void showProfile(){
     @Override
     public boolean specialAbility(Enemy enemy) {
         if (this.ultimateCooldown == 0 && this.leftArrow > 0) {
-            int totalDamage = this.leftArrow * this.damage;
-            enemy.takeDamage(totalDamage);
-            System.out.println("ULTIMATE: Arrow Rain! You shoot your " + this.leftArrow + " arrow at the same time: " + totalDamage + " damage!");
+            int ultimateDamage = this.leftArrow * this.damage;
+            enemy.takeDamage(ultimateDamage);
+            System.out.println("ULTIMATE: Arrow Rain! You shoot your " + this.leftArrow + " arrow at the same time: " + ultimateDamage + " damage!");
             this.leftArrow = 0;
             this.ultimateCooldown = 5;
             return true;

src/DMGBuff.java

@@ -2,6 +2,6 @@ public class DMGBuff extends PlayerDecorator {
     public DMGBuff(Player p) {
         super(p);
         this.wrappedPlayer.damage += 2;
-        this.className = this.wrappedPlayer.className + "DMGBuff";
+        this.wrappedPlayer.className = p.className + " (DMG Buff)";
     }
-}
+}

src/Game.java

@@ -84,9 +84,10 @@ public static void play(Player p, Scanner input, Random rand) {
 
                 if (choice == 1) {
                     stage++;
-                    p.health += 3;
-                    if (p.getHealth() < p.getMaxHealth()) p.setHealth(p.getHealth() + 3);
-                    System.out.println("You rested for a moment. HP restored by 3.");
+                    int newHealth = Math.min(p.getHealth() + 3, p.getMaxHealth());
+                    int amountHealed = newHealth - p.getHealth();
+                    p.setHealth(newHealth);
+                    System.out.println("You rested for a moment. HP restored by " + amountHealed + ".");
                 } else {
                     System.out.println("You retired as a legendary hero at Stage " + stage + "!");
                     playing = false;

src/HPBuff.java

@@ -1,8 +1,8 @@
 public class HPBuff extends PlayerDecorator {
     public HPBuff(Player p) {
         super(p);
+        this.wrappedPlayer.maxHealth += 3;
         this.wrappedPlayer.health += 3;
-        this.health = maxHealth;
-        this.className = this.wrappedPlayer.className + "HPBuff";
+        this.wrappedPlayer.className = p.className + " (HP Buff)";
     }
-}
+}

src/Knight.java

@@ -8,7 +8,7 @@ public Knight(String nickname) {
     }
 
     public boolean attack(Enemy enemy) {
-        enemy.HP -= this.damage;
+        enemy.takeDamage(this.damage);
         System.out.println("You hit enemy " + this.damage + " damage," +
                 " Enemy HP left is:" + enemy.HP);
         this.damage++;

src/Tank.java

@@ -14,7 +14,7 @@ public Tank(String nickname) {
     }
 
     public boolean attack(Enemy enemy){
-        enemy.HP -= this.damage;
+        enemy.takeDamage(this.damage);
         System.out.println("You hit enemy " + this.damage + " damage," +
                 " Enemy HP left is:" + enemy.HP);
         return true;