Considering that Ancient Mew has a different back-side than all other
pokemon cards and its text is written in what looks like "Egyptian", would
it be considered playable? I, myself was looking forward to making a speed
deck involving four of them, but I still am not sure on the rules specifying
to this card.
Due to the different backing, no matter how much we might want to, Egyptian Mew is NOT playable. Sorry.
WotC Errata: WotC has ruled that in an opaque sleave, Egyptian Mew IS playable. Since the card was not playable in Japan, we believed it would not be legal here, but for some reason, WotC decided against that. Oh well - looks like we have egg on our face.