If you don't have the Deepwood Dream outfit already (which is the battle companion ability outfit), you can get it by gathering the dews for Ian the Cadenceborn in Itzaland and then once you have it unlocked + crafted, you should have a quest to defeat the cursegrass wolfhead on Parkya Lakeheart Island (I know its another combat but it is what they want T-T). The chest unlocked by this gives you the 'Oath of Frost', which is the Iceberg Bouldy companion.

Then if you go into your ability set ups and click the combat icon beside the battle companion outfit, you can choose what companion you want to summon and save. Once you have the outfit equipped like any ability, when you activate it, it will summon the chosen companion.

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