Pokémon TCG: Sword and Shield had a long run with Crown Zenith wrapping up the series with some of the best cards of the era. This series introduced V, VMAX, and VSTAR cards with a heavy focus on cards surrounding these types of cards, which will be retired at the end of Crown Zenith and no longer be produced. This is the best time to purchase some Sword and Shield cards before Scarlet and Violet take off.
https://screenrant.com/best-cards-pokemon-tcg-sword-shield-crown-zenith/