Since not all details are confirmed let us know information you get by submitting comment or screenshot in a thread at the bottom of the page
You need to enter the Card Studio to change card sleeves and game mat. The facility is also used to edit deck.
When visit the studio, you will see the menu, then choose Customization to see available accessories and to use them.
Only acquired card sleeves and game mat are displayed. Select the one to make your duel field cool.
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