From October 15th to 30th, Pokemon HeartGold and Pokemon SoulSilver players will be able to obtain a special Mew. This rare psychic Pokemon is incredibly powerful and its stats are evenly distributed, so with proper EV training it can serve pretty much any role you can think of. Furthermore, its move pool is unrestricted, making it even more versatile and tougher to predict. Here are some details from the official press release: