Harry Potter and the Chinese Overseas Students at the Hogwarts School of Witchcraft and Wizardry, just one of the many bootleg Harry Potters profiled at the New York Times. Here's the summary of the one that is plainly the best, Harry Potter and the Leopard-Walk-Up-to-Dragon:

Harry becomes a fat, hairy dwarf after being caught in a “sour and sweet rain”; he loses all his magic and can get it back only by obtaining the magic ring. After he does, Harry becomes a dragon that fights evil. Voldemort has an even more powerful brother who makes trouble for Harry.