Harry decided that getting into an argument with Snape would be pointless since he was about to die ANYWAY, so Harry simply said "Cheers" and drank some of the concoction that he had carelessly created.
Harry soon found himself rocketing up in size by hundreds of feet, growing green, scaly skin and big fangs and claws, destroying the entierity of Hogwarts in the process. Harry didn't know WHAT had just happened, but he suddenly had an instinctual urge to flatten Tokyo.
Harry thus stomped his way across land and sea, causing chaos and destruction in his wake. When he finally got to Tokyo, he went on an almighty rampage the likes of which had never been seen. Unfortunately, Harry was then captured and executed for copyright infringement.
YOU HAVE DIED
Not satisfied with your ending? Go back to Chapter 1 to start all over!