Pokemon TCG: Galar Collection - Rules of Play says:
In addition to three awesome foil promo cards featuring the adorable Grookey, Scorbunny, and Sobble, each Galar Collection includes one of two foil oversize cards featuring the newly discovered Legendary Pokémon Zacian or Zamazenta. These cards showcase the upcoming Pokémon V mechanic! In addition, the collection features one of three glossy pins featuring Grookey, Scorbunny, or Sobble, along with four Pokémon TCG booster packs.