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Weird, but forest-themed pokemon
Walk through the Lost Woods essentially to find a missing Teddiursa, it joins your team (temporarily/follows you if stars has follows) until you find a totem Ursaring running about the forest, it sees you have it's child and becomes enraged, initiating the battle. Ursaring has attack boosted and summons shroomish/vigoroth/wormadam, two of which can activate Ursaring's quick feet allowing it to potentially sweep your team and be a bigger pain in the ass than Lurantis was for most.
You get Normalium Z and TM Protect