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Hey guys, I'm currently having trouble trying to create a commander deck in XMage with partner commanders. I have both commanders in the sideboard (Thrasios and Vial Smasher), but the validator is still giving me errors saying 'Commander without Partner'. So, how do you set partner commanders in XMage?

You should be able to just put them in your sideboard. Make sure you only have 98 cards in main deck.