Jolteon

Jolteon is card 20 in the Jungle set (1999), a rare Pokémon card with the Lightning type, so it has a yellow card frame. In Tall Grass Club you'll find it about 1 in 25 packs when you open free Jungle packs.

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

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