Strength Expansion Pack: Peerless Fighters is a subset containing 96 cards and was first released in Japan on March 19, 2021. Each booster pack contains five cards. Several Pokémon with Galar regional forms debut in this subset following their appearance in The Crown Tundra DLC for Pokémon Sword and Shield, including Slowking, Articuno, Zapdos, and Moltres, all of which appear as Pokémon V and receive Special Full Art prints. The subset once again features the Wushu Pokémon Urshifu in its Single Strike and Rapid Strike Style, this time as non-variant Darkness and Water-type Stage 1 Pokémon, respectively. Their inclusion also heralds the TCG debut of their base form, Kubfu. The two forms of Urshifu support the Single Strike and Rapid Strike mechanics, as do numerous other Pokémon and Trainer cards in the subset.
The subset was later released in Taiwan and Hong Kong on April 2, 2021, in South Korea on April 21, 2021, in Thailand on April 30, 2021, and in Indonesia on July 2, 2021.