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Battle log and mulligan

According to the rule book when one player takes a mulligan and the other doesn't, the other player must set up first his side of the board and then checks the opponent hand to make sure they didn't have a basic pokémon.
Well there is a bug where you can see the opponents hand in the battle log before you place down a pokémon 😅 (in other words you can understand what you are playing against before you place down your 1st basic pokémon)