I DO NOT believe this sealed deck is Shadowless.
The 1999 Pokémon Overgrowth Theme Deck is a vintage factory-sealed product that includes 60 standard-sized cards from the Pokémon TCG Base Set. Illustrated by Keiji Kinebuchi and manufactured by Wizards of the Coast, this English-language deck is retro-themed, perfect for collectors or fans of the Pokémon trading card game. It is a nostalgic piece of memorabilia from the Pokémon League era, making it a valuable addition to any Pokémon card collection.