There are a bunch of useful items hidden in Pokémon Sword and Shield, including the legendary Choice Specs.
Choice Specs is an item that vastly raises a Pokemon’s Special Attack but only allows them to use a single move throughout a fight. So if you have an instant KO Pokémon, this item is definitely worth grabbing.
If you want to get a pair of Choice Specs, you’ll first need to get far in the game.
After beating the seventh gym leader, you can return to the Gym Challenge and cycle down the street in Spikemuth. You’ll be able to go to the back of the gym leader’s stage, where you’ll see a Poké Ball item.
The Choice Specs will be there for you to grab at your leisure.