Origins of Vintage Pokémon › Promos
Mewtwo
How it was given out: CoroCoro insert (glossy).
Promo 5 of 61 known unnumbered promos released before English Base Set (Oct 1996 to Jan 1999).
Unofficial fan reference. Pokémon and card artwork © Nintendo, Creatures, GAME FREAK and The Pokémon Company.