The popular painlands are returning to Magic: The Gathering’s Dominaria United with reprints for Adarkar Wastes, Caves of Koilos, Karplusan Forest, Shivan Reef, Sulfurous Springs, and Yavimaya Coast. However, only six of the ten painlands have arrived in the most recent set. The remaining four painlands will appear in The Brothers’ War due out later in November.But why these particular six? Why not Battlefield Forge or Underground River? For the answer, we turn to the lead designer on Dominaria United, Ethan Fleischer, who explained that at least part of the reason was because some of these cards reference locations that didn’t even exist during the time of The Brothers’ War."There were no such places named Adarkar Wastes, Karplusan Forest, or Yavimaya back then," explained Fleischer. "So they needed to be in Dominaria United. Once that was decided, we added two more lands to balance out the colors. It would have been nice for the Caves of Koilos to be in the Brothers' War set, since they played a bigger role in that story, but they certainly still exist in present day Dominaria."
Being one of the most well-established planes, locations in Dominaria have evolved over time. Several such spots mentioned in these cards, such as the Adarkar Wastes, only exist because of the terrible battles of The Brothers' War. So it could only make sense for them to be in Dominaria United, which is Magic’s most "current" set chronologically speaking.
But don’t worry--the remaining painlands will return with The Brothers' War on November 18. And if the current rumors hold, we might even get some popular artifacts reprinted as well. A recent Amazon listing for Brothers' War draft boosters revealed an unusual rarity breakdown that could hint to the return of Strixhaven's Mystical Archive feature, only for artifacts instead of instants and sorceries.