以下のコードをコピーして貼り付ければゲームができます。

Private i As Byte, i2 As Byte, i3 As Byte
Private Num As Byte
Private Number(1 To 25) As Byte
Private StartTime As Long
Private GameFrag As Boolean

Private Sub Worksheet_SelectionChange(ByVal Target As Excel.Range)
If GameFrag = True And Cells(2, 2).Interior.ColorIndex > 30 Then GoTo Ido
    Randomize
    GameFrag = True
    i = 0: i3 = 1
    Cells(1, 2) = "15･ﾑ･ｺ･・quot;
    Cells(1, 2).Font.Size = 30
    Rows("2:5").RowHeight = 55
    Range("B2:E5").Font.Size = 35
    Range("B2:E5").Font.ColorIndex = 5
    Range("B2:E5").HorizontalAlignment = xlCenter
    Range("B2:E5").VerticalAlignment = xlCenter
    Range("B2:E5").Borders(xlEdgeLeft).LineStyle = xlContinuous
    Range("B2:E5").Borders(xlEdgeTop).LineStyle = xlContinuous
    Range("B2:E5").Borders(xlEdgeBottom).LineStyle = xlContinuous
    Range("B2:E5").Borders(xlEdgeRight).LineStyle = xlContinuous
    Range("B2:E5").Borders(xlInsideVertical).LineStyle = xlContinuous
    Range("B2:E5").Borders(xlInsideHorizontal).LineStyle = xlContinuous
    Num = Int(3 * Rnd) + 1
Select Case Num
    Case 1: Range("B2:E5").Interior.ColorIndex = 36
    Case 2: Range("B2:E5").Interior.ColorIndex = 35
    Case 3: Range("B2:E5").Interior.ColorIndex = 34
End Select
Do Until i = 15
    i = i + 1
1:
    Num = Int(15 * Rnd) + 1
    For i2 = 1 To i
        If Num = Number(i2) Then
            GoTo 1
        End If
    Next i2
    Number(i) = Num
Loop
For i = 2 To 5
    For i2 = 2 To 5
        Cells(i, i2) = Number(i3)
        i3 = i3 + 1
    Next i2
Next i
Range("E5").ClearContents
StartTime = Timer
Ido:
If ActiveCell.Interior.ColorIndex = xlNone Or GameFrag = False Then Exit Sub
If ActiveCell.Offset(1, 0).Interior.ColorIndex > 30 And ActiveCell.Offset(1, 0) = "" Then
    ActiveCell.Offset(1, 0) = ActiveCell.Value
    Activecell = "": ActiveCell.ClearContents
End If
If ActiveCell.Offset(-1, 0).Interior.ColorIndex > 30 And ActiveCell.Offset(-1, 0) = "" Then
    ActiveCell.Offset(-1, 0) = ActiveCell.Value
    Activecell = "": ActiveCell.ClearContents
End If
If ActiveCell.Interior.ColorIndex = xlNone Then Exit Sub
If ActiveCell.Offset(0, 1).Interior.ColorIndex > 30 And ActiveCell.Offset(0, 1) = "" Then
    ActiveCell.Offset(0, 1) = ActiveCell.Value
    Activecell = "": ActiveCell.ClearContents
End If
If ActiveCell.Offset(0, -1).Interior.ColorIndex > 30 And ActiveCell.Offset(0, -1) = "" Then
    ActiveCell.Offset(0, -1) = ActiveCell.Value
    Activecell = "": ActiveCell.ClearContents
End If
i3 = 1
For i = 2 To 5
    For i2 = 2 To 5
        Number(i3) = i3
        If Cells(i, i2) <> Number(i3) Then Exit Sub
            i3 = i3 + 1
        If i3 = 16 Then
            MsgBox Int(Timer - StartTime) & "ﾉﾃ"
            GameFrag = False
        End If
    Next i2
Next i
End Sub