Stellar Crystal is the ninth Scarlet & Violet expansion to be released in the Simplified Chinese language version of the Pokémon Trading Card Game. The expansion introduces elements from Pokémon Scarlet and Violet's The Indigo Disk expansion, including Stellar Tera Pokémon ex, a special type of Tera Pokémon ex featuring Terastallized Pokémon with the Stellar type. It also includes new Pokémon introduced in the expansion, such as Terapagos and Archaludon, and new characters, such as Briar, Lacey, and Crispin. Most of the set's cards originate from the Japanese Stellar Miracle and Super Electric Breaker sets, as well as a small number from other sets and products.
Cards are available in two different types of booster packs:
5-card booster packs; one card is either Reverse Holofoil or have a rarity of or higher;
20-card booster packs; six cards are either Reverse Holofoil or have a rarity of of higher.
Each of the 177 common, uncommon, and rare cards in the expansion come in two Reverse Holofoil variants - one with a Poké Ball motif, and a rarer one with a Master Ball motif.