Fire Emblem Cipher B21: The Firestorm (Booster Pack)
- Contents: 10 cards
- Variety: 48 Normal, 24 High Normal, 16 Rare, 12 Super Rare, 3 Hero Rares
- Alternates: 6 Alternate Foil Prints
- Featured Games: Three Houses, Binding Blade, Heroes
- Released: June 25, 2020
- Language: Japanese
This is the 21st booster set for the Fire Emblem 0 (Cipher) Trading Card game. This very popular TCG in Japan is starting to expand worldwide. Enjoy playing against your friends with all your favourite Fire Emblem characters!