diff --git a/03_Animal/vbnet/Animal.Tests/Animal.Tests.vbproj b/03_Animal/vbnet/Animal.Tests/Animal.Tests.vbproj
index 05d00314..62a341e9 100644
--- a/03_Animal/vbnet/Animal.Tests/Animal.Tests.vbproj
+++ b/03_Animal/vbnet/Animal.Tests/Animal.Tests.vbproj
@@ -3,12 +3,12 @@
   <PropertyGroup>
     <RootNamespace>Animal.Tests</RootNamespace>
     <TargetFramework>net6.0</TargetFramework>
-
     <IsPackable>false</IsPackable>
+    <OptionStrict>On</OptionStrict>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.11.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
@@ -20,4 +20,8 @@
     </PackageReference>
   </ItemGroup>
 
+  <ItemGroup>
+    <ProjectReference Include="..\Animal\Animal.vbproj" />
+  </ItemGroup>
+
 </Project>
diff --git a/03_Animal/vbnet/Animal.Tests/MockConsole.vb b/03_Animal/vbnet/Animal.Tests/MockConsole.vb
new file mode 100644
index 00000000..a78dc50f
--- /dev/null
+++ b/03_Animal/vbnet/Animal.Tests/MockConsole.vb
@@ -0,0 +1,65 @@
+Imports System.IO
+
+Public Class MockConsole
+    Inherits ConsoleAdapterBase
+
+    Private inputs As Queue(Of String)
+    Public ReadOnly Lines As New List(Of (line As String, centered As Boolean)) From {
+        ("", False)
+    }
+
+    ' TODO it's possible to clear all the lines, and we'd have to check once again in WriteString and WriteCenteredLine if there are any lines
+
+    Sub New(Inputs As IEnumerable(Of String))
+        Me.inputs = New Queue(Of String)(Inputs)
+    End Sub
+
+    Private Sub CheckLinesInitialized()
+        If Lines.Count = 0 Then Lines.Add(("", False))
+    End Sub
+
+    Private Sub WriteString(s As String, Optional centered As Boolean = False)
+        If s Is Nothing Then Return
+        CheckLinesInitialized()
+        s.Split(Environment.NewLine).ForEach(Sub(line, index)
+                                                 If index = 0 Then
+                                                     Dim currentLast = Lines(Lines.Count - 1)
+                                                     ' centered should never come from the current last line
+                                                     ' if WriteCenteredLine is called, it immediately creates a new line
+                                                     Lines(Lines.Count - 1) = (currentLast.line + line, centered)
+                                                 Else
+                                                     Lines.Add((line, centered))
+                                                 End If
+                                             End Sub)
+    End Sub
+
+    Public Overrides Sub Write(value As Object)
+        WriteString(value?.ToString)
+    End Sub
+
+    Public Overrides Sub WriteLine(value As Object)
+        WriteString(value?.ToString)
+        WriteLine()
+    End Sub
+
+    Public Overrides Sub WriteLine()
+        Lines.Add(("", False))
+    End Sub
+
+    Public Overrides Sub WriteCenteredLine(value As Object)
+        If Lines.Count = 0 Then Lines.Add(("", False))
+        Dim currentLast = Lines(Lines.Count - 1).line
+        If currentLast.Length > 0 Then Throw New InvalidOperationException("Can only write centered line if cursor is at start of line.")
+        WriteString(value?.ToString, True)
+        WriteLine()
+    End Sub
+
+    Public Overrides Function ReadLine() As String
+        ' Indicates the end of a test run, for programs which loop endlessly
+        If inputs.Count = 0 Then Throw New EndOfStreamException("End of inputs")
+
+        Dim nextInput = inputs.Dequeue.Trim
+        WriteLine(nextInput)
+        Return nextInput
+    End Function
+End Class
diff --git a/03_Animal/vbnet/Animal.Tests/TestContainer.vb b/03_Animal/vbnet/Animal.Tests/TestContainer.vb
new file mode 100644
index 00000000..3aed862a
--- /dev/null
+++ b/03_Animal/vbnet/Animal.Tests/TestContainer.vb
@@ -0,0 +1,80 @@
+Imports Xunit
+Imports Animal
+Imports System.IO
+
+Public Class TestContainer
+    Private Shared Function ResponseVariantExpander(src As IEnumerable(Of String)) As TheoryData(Of String)
+        Dim theoryData = New TheoryData(Of String)
+        src.
+            SelectMany(Function(x) {x, x.Substring(0, 1)}).
+            SelectMany(Function(x) {
+                x,
+                x.ToUpperInvariant,
+                x.ToLowerInvariant,
+                x.ToTitleCase,
+                x.ToReverseCase
+            }).
+            Distinct.
+            ForEach(Sub(x) theoryData.Add(x))
+        Return theoryData
+    End Function
+    Private Shared YesVariantsThepryData As TheoryData(Of String) = ResponseVariantExpander({"yes", "true", "1"})
+    Private Shared Function YesVariants() As TheoryData(Of String)
+        Return YesVariantsThepryData
+    End Function
+    Private Shared NoVariantsThepryData As TheoryData(Of String) = ResponseVariantExpander({"no", "false", "0"})
+    Private Shared Function NoVariants() As TheoryData(Of String)
+        Return NoVariantsThepryData
+    End Function
+
+    ''' <summary>Test LIST variants</summary>
+    <Theory>
+    <InlineData("LIST")>
+    <InlineData("list")>
+    <InlineData("List")>
+    <InlineData("lIST")>
+    Sub List(listResponse As String)
+        Dim console As New MockConsole({listResponse})
+        Dim game As New Game(console)
+        Assert.Throws(Of EndOfStreamException)(Sub() game.BeginLoop())
+        Assert.Equal(
+            {
+                "ANIMALS I ALREADY KNOW ARE:",
+                "FISH           BIRD           "
+            },
+            console.Lines.Slice(-4, -2).Select(Function(x) x.line)
+        )
+    End Sub
+
+    '' <summary>Test YES variants</summary>
+    <Theory>
+    <MemberData(NameOf(YesVariants))>
+    Sub YesVariant(yesVariant As String)
+        Dim console As New MockConsole({yesVariant})
+        Dim game As New Game(console)
+        Assert.Throws(Of EndOfStreamException)(Sub() game.BeginLoop())
+        Assert.Equal(
+            {
+                $"ARE YOU THINKING OF AN ANIMAL? {yesVariant}",
+                "DOES IT SWIM? "
+            },
+            console.Lines.Slice(-2, 0).Select(Function(x) x.line)
+        )
+    End Sub
+
+    '' <summary>Test NO variants</summary>
+    <Theory>
+    <MemberData(NameOf(NoVariants))>
+    Sub NoVariant(noVariant As String)
+        Dim console As New MockConsole({"y", noVariant})
+        Dim game As New Game(console)
+        Assert.Throws(Of EndOfStreamException)(Sub() game.BeginLoop())
+        Assert.Equal(
+            {
+                $"DOES IT SWIM? {noVariant}",
+                "IS IT A BIRD? "
+            },
+            console.Lines.Slice(-2, 0).Select(Function(x) x.line)
+        )
+    End Sub
+End Class
diff --git a/03_Animal/vbnet/Animal.Tests/UnitTest1.vb b/03_Animal/vbnet/Animal.Tests/UnitTest1.vb
deleted file mode 100644
index fe32490e..00000000
--- a/03_Animal/vbnet/Animal.Tests/UnitTest1.vb
+++ /dev/null
@@ -1,12 +0,0 @@
-Imports System
-Imports Xunit
-
-Namespace Animal.Tests
-    Public Class UnitTest1
-        <Fact>
-        Sub TestSub()
-
-        End Sub
-    End Class
-End Namespace
-
diff --git a/03_Animal/vbnet/Animal/Shared/ConsoleAdapter.vb b/03_Animal/vbnet/Animal/Shared/ConsoleAdapter.vb
index 132f1968..f49394e0 100644
--- a/03_Animal/vbnet/Animal/Shared/ConsoleAdapter.vb
+++ b/03_Animal/vbnet/Animal/Shared/ConsoleAdapter.vb
@@ -14,6 +14,7 @@
     End Sub
 
     Public Overrides Sub WriteCenteredLine(value As Object)
+        If Console.CursorLeft <> 0 Then Throw New InvalidOperationException("Can only write centered line if cursor is at start of line.")
         Dim toWrite = If(value?.ToString, "")
         Console.WriteLine($"{Space((Console.WindowWidth - toWrite.Length) \ 2)}{toWrite}")
     End Sub
diff --git a/03_Animal/vbnet/Animal/Shared/Extensions.vb b/03_Animal/vbnet/Animal/Shared/Extensions.vb
index 83d1914b..e10df441 100644
--- a/03_Animal/vbnet/Animal/Shared/Extensions.vb
+++ b/03_Animal/vbnet/Animal/Shared/Extensions.vb
@@ -1,6 +1,11 @@
 Imports System.Runtime.CompilerServices
 
 Public Module Extensions
+    <Extension> Public Sub ForEach(Of T)(src As IEnumerable(Of T), action As Action(Of T))
+        For Each x In src
+            action(x)
+        Next
+    End Sub
     <Extension> Public Sub ForEach(Of T)(src As IEnumerable(Of T), action As Action(Of T, Integer))
         Dim index As Integer
         For Each x In src
@@ -18,4 +23,28 @@ Public Module Extensions
         If Not s.EndsWith(toAppend, StringComparison.OrdinalIgnoreCase) Then s += toAppend
         Return s
     End Function
+
+    <Extension> Public Function ToTitleCase(s As String) As String
+        If s Is Nothing Then Return Nothing
+        Return Char.ToUpperInvariant(s(0)) + s.Substring(1).ToUpperInvariant
+    End Function
+
+    ' https://stackoverflow.com/a/3681580/111794
+    <Extension> Public Function ToReverseCase(s As String) As String
+        If s Is Nothing Then Return Nothing
+        Return New String(s.Select(Function(c) If(
+            Not Char.IsLetter(c),
+            c,
+            If(
+                Char.IsUpper(c), Char.ToLowerInvariant(c), Char.ToUpperInvariant(c)
+            )
+            )).ToArray)
+    End Function
+
+    ' https://stackoverflow.com/a/58132204/111794
+    <Extension> Public Function Slice(Of T)(lst As IList(Of T), start As Integer, [end] As Integer) As T()
+        start = If(start >= 0, start, lst.Count + start)
+        [end] = If([end] > 0, [end], lst.Count + [end])
+        Return lst.Skip(start).Take([end] - start).ToArray
+    End Function
 End Module