Ditto

Ditto is card 18 in the Fossil set (1999), a rare Pokémon card with the Colorless type, so it has a white card frame. In Tall Grass Club you'll find it about 1 in 23 packs when you open free Fossil packs.

Every pack has one rare slot, so this card takes a little luck.

Want to know more about the Pokémon? See Ditto in the Pokédex.