When I look at the formats page, there are seven listed Commander, Standard, Vintage, Legacy, Modern, Block, Team Unified Constructed

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This game improved upon the original base set, in that that are army-building options available with just this set
Players might not have the time or space for the subgame, so Shahrazad got itself banned to avoid problems in tournaments
Found an error or omission
With a steady stream of lands in graveyards, its like a more resilient Birds of Paradise at a base level