Tournament rule 602.4.a.7
A sealed deck’s sideboard is every card provided to the player as part of the competition that isn’t used in their starting deck configuration, unless otherwise specified. See 403 for more information on sideboards.
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A sealed deck’s sideboard is every card provided to the player as part of the competition that isn’t used in their starting deck configuration, unless otherwise specified. See 403 for more information on sideboards.