In addition to your trainer's own personal League Card, you will also collect the League Cards for all the Main Characters and Gym Leaders found in Pokemon Sword & Shield. These League Cards will give you a basic biography of the character, and almost all of these characters will have a common League Card and a Rare League Card for you to obtain. You will actually add all but three Main Character League Cards to your League Card Album simply by completing both the Main Story and the Post Game Story - Simple Enough!
But if you would like to add Chairmen Rose's Rare League Card to you collection, you will need to talk with Oleana in the Galar Mine after the Main Story. If you would like to obtain Ball Guy's League Card, you will need to talk to him outside Motostoke Stadium after you defeat the Main Story. And finally, if you want to nab Leon's Rare League Card, you will need to defeat him just once at the Battle Tower. There are twenty-seven of these League Cards to be obtained in each game.
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