WotC will eliminate Set and Draft Boosters starting with Murders at Karlov Manor, and introduce Play Boosters, a hybrid of the two. This continues the trend of WotC consolidating booster pack types for Standard sets, as they had quietly done away with in-set Jumpstart Boosters with Wilds of Eldraine (see "'Magic: The Gathering - Wilds of Eldraine'"). The new boosters are aimed at being fun to open as well as optimized for Limited play, but their primary purpose seems to be reducing consumer confusion over the number of booster product choices available per set.The Lost Caverns of Ixalan").
The price per pack will also be going up. Lead Designer Mark Rosewater confirmed, in the blog introducing Play Boosters, that "...yes, you will be paying slightly more (per pack), but you’ll likely be getting more value out of the boosters." This proposed price hike seems to contradict one of the Play Boosters' initial goals, which is being ideal for Limited play. A price increase would inherently make Limited more expensive to play as stores would have to charge more for tournaments to cover the price of the new product.
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