Since the Alola region, a new feature called «Regional Forms» was introduced to the Pokemon world. This would take Pokemon from pre-existing generations and give them a different look and Typing depending on the region the Pokemon came from. For example, Vulpix has orange/brown fur and is a Fire-type, but the Vulpix from Alola are white-furred and have the Ice-typing instead. Pokemon Legends: Arceus recently gave a regional variant to Johto's Sneasel, a Dark/Ice-type Pokemon.
In Pokemon Legends: Arceus, Sneasel goes from a Dark/Ice-type to a Fighting/Poison-type. Interestingly, Hisuin Sneasel won't evolve into Weavile. Instead, it will become Sneasler, a new Pokemon from the Hisui region. Fortunately for those that prefer Weavile, the original Sneasel is a part of the Hisui Pokedex.
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After calming the Noble Kleavor in the Obsidian Fieldlands, strange «domes' will start randomly appearing around Hisui. These are referred to in-game as Space-time Distortions, and they are home to rare Pokemon and rare items. Space-time Distortions take some time to completely form, but players will receive a notification at the top of their screen when it's fully appeared.
One of the Pokemon that appears in space-time distortions is the original Sneasel. However, it only spawns in the distortions that pop up in the Obsidian Fieldlands. Since there will be many other Pokemon, it may be hard to catch Sneasel. The best strategy is to circle around it with Wyrdeer and try to lure other Pokemon away. Then, battle Sneasel and catch it with a Great Ball or Ultra Ball.
Since Sneasel is a Pokemon with gender differences, trainers will need to catch the male and female version of both Sneasel forms
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