When the Isle of Armor and Crown Tundra were first announced, it was revealed that both Slowbro and Slowking would be receiving Galarian Forms. Galarian Slowbro was exclusive to the Isle of Armor, while Galarian Slowking can only be obtained within the Crown Tundra. One the Isle of Armor, players had exchange eight Galarica Twigs with the person found in the Workout Sea in order to obtain the Galarica Cuff. This is the item that is needed to evolve Galarian Slowpoke into Galarian Slowbro. A similar method is used in the Crown Tundra to obtained Galarian Slowking.
In order to obtain Galarian Slowking, players will first have to collect a total of fifteen Galarica Twigs. With them, players will then have to travel to Roaring-Sea Caves. There, you will find a woman in the northern part of the caves that can only be accessed via the Frigid Sea. In exchange for the fifteen Galarica Twigs, she will give you a Galarica Wreath. This evolutionary item will help you evolve Galarian Slowpoke into Galarian Slowking.
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