From the Publisher: 

Build two decks with a friend—and then play right away! This Pokémon TCG: Sword & Shield—Silver Tempest Build & Battle Stadium contains a massive set of cards, including two Build & Battle Boxes. Each Build & Battle Box contains four booster packs and a 40-card deck that includes an exclusive foil card. You can play these decks right out of the box, or enhance them with cards from the booster packs. Get ready to face your opponents in the Build & Battle Stadium!

Contents:
2 individual Build & Battle Boxes, each containing a ready-to-play 40-card deck
Each deck includes 1 of 4 foil promo cards
4 additional Sword & Shield—Silver Tempest booster packs, so you get 12 in all
121 basic Energy cards
6 damage-counter dice
1 competition-legal coin-flip die
2 acrylic condition markers
A collector’s box to hold everything