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071 Thetis, Medicinal Merperson

Jarrod Garripoli
Location Hydropolis; Inside the item shop
Chapter 7
4970 Exp, 1610G, Superior Sixth Censer (x2), Thetis as Citizen

Thetis, a doctor, is always busy attending to patients, but has recently discovered a formula that allows merfolk to stay on land for extended periods without getting sick. She needs one more ingredient, which is some deep seawater that can be found in Tidewash Cave. This particular cave can be found to the northwest of Capstan, but you will need to cross the rift in order to get to it. The closest spot to cross is southwest of Hydropolis and once you do, follow the rift to the west and then north when you get to land. The cave is in a little inlet, which can be hard to see, since the sky will be dark.

(1 of 2) The location of Tidewash Cave on the world map

The location of Tidewash Cave on the world map (left), as well as the seawater you need to pick up inside of the cave (right)

There is a Trip Door at the top of the island with Tidewash Cave (Tidewash Cave), so activate that before you head inside. Head straight south, past the first group of enemies (there’s a chest in the same room with Determined Rakish Boots inside) and then west to find an area with a Dreamer’s Door. The item you’re looking for is in this section, as evidenced by the blue circle. You’re looking for a blue sparkle on the ground, which is on the southern side of the room, yielding a jar of Deep Seawater. Bring this back to Thetis in Hydropolis to finish the quest and gain a new citizen.


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Guide Information

  • Publisher
    Bandai Namco Entertainment
  • Platforms,
    PC, PS4
  • Genre
  • Guide Release
    6 April 2018
  • Last Updated
    7 December 2020
    Version History
  • Guide Author

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You are Evan Pettiwhisker Tildrum, a young boy that is to become the king of Ding Dong Dell. After the passing of his father, he was to inherit the throne, but a coup d’etat by his truster adviser put his life in danger. Thanks to a mysterious stranger named Roland, he is saved, but not without losing his kingdom in the process. Evan has decided to start a new kingdom, one where everyone can live in peace, with the help of his newly acquired friend, Roland.

This guide contains the following:

  • A detailed walkthrough for the main story, from the beginning to the end
  • A guide to all 175 Sidequests
  • Locations for every Citizen, Higgledy Stone, Songbook and other collectibles
  • A comprehensive trophy guide that will net you another shiny platinum

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