Completing themed missions will allow you to collect unique pawns and frames by answering topical questions in your Mountain Track and Toad kingdom games.
Once you've completed a mission, you will have to claim your prize to find the collectible in the Inventory. To do this, you will need to access the "Missions" section by tapping on the map icon on your home screen and select the "Themed" tab. There, you will find the list of active missions and, upon locating the one you have completed, you will be able to press the "Collect" button on the right-hand side.
You will be able to equip the corresponding pawn or frame once you select it and click on the "Equip" option.