A few brand-new challenges have begun in both Pokémon Shuffle and Pokémon Shuffle Mobile. First is a new Ultra Challenge featuring Xurkitree. This stage can only be played a maximum of 10 times and requires 20,000 coins. It runs until November 7, 2017. Next, a stage for Palossand has also begun and runs until November 14, 2017. Finally, the Litten and Drifblim stages have begun repeat runs. All of these additions require the software version 1.4.27 to download.
Source: Serebii
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