Go talk to Mara Sov by taking the portal.
Either way, both will require either party member to be levelled high enough before you can gain the following bits of info.
Undertow Cove is in North Rippletide Coast, to the right of Rippletide.
Octopath Traveler Weapons and Armor There are a total of 7 different weapons that exist in Octopath Traveler.
Speak to the to engage him in battle.
Primeval Bow of Storms Stats Phys.