diff --git a/exercises/concept/wizards-and-warriors/.docs/instructions.md b/exercises/concept/wizards-and-warriors/.docs/instructions.md
index 59d9e7ccf3..b450a1977f 100644
--- a/exercises/concept/wizards-and-warriors/.docs/instructions.md
+++ b/exercises/concept/wizards-and-warriors/.docs/instructions.md
@@ -45,6 +45,8 @@ Implement the `Wizard.PrepareSpell()` method to allow a Wizard to prepare a spel
 ```csharp
 var wizard = new Wizard();
 wizard.PrepareSpell();
+wizard.Vulnerable();
+// => false
 ```
 
 ## 4. Make Wizards vulnerable when not having prepared a spell
diff --git a/exercises/concept/wizards-and-warriors/WizardsAndWarriorsTests.cs b/exercises/concept/wizards-and-warriors/WizardsAndWarriorsTests.cs
index 71348733b4..ed362d9fb0 100644
--- a/exercises/concept/wizards-and-warriors/WizardsAndWarriorsTests.cs
+++ b/exercises/concept/wizards-and-warriors/WizardsAndWarriorsTests.cs
@@ -27,6 +27,15 @@ public void Warrior_is_not_vulnerable()
         Assert.False(warrior.Vulnerable());
     }
 
+    [Fact]
+    [Task(3)]
+    public void Wizard_is_not_vulnerable_after_preparing_spell()
+    {
+        var wizard = new Wizard();
+        wizard.PrepareSpell();
+        Assert.False(wizard.Vulnerable());
+    }
+    
     [Fact]
     [Task(4)]
     public void Wizard_is_vulnerable()