The Ancient Mew Card was a 2nd Promo and movie promotion that came with admission to "The Power of One".
It is a Psychic-type with 30HP, and has a move called "Psyche", that does 40 damage. It requires 2 Psychic energies. It also has a retreat cost of two.
The bottom text has two passages. One reading, "Little God or Evil?", ad the other reading, "Birth, Enthronement, Right of Succession and Death". Pretty haunting, huh?