During The Shadow Under Neketaka quest your party will reach the Watershapers Guild located in Periki's Overlook (M15) - this quest can be received from Queen Onekaza II after you complete A Distant Light quest (reach Hasongo island). A Distant Light is one of the main quests in Pillars of Eternity 2 Deadfire.
During The Shadow Under Neketaka quest your party reaches the Watershapers Guild - this is a small location where you can find Rod of the Deep Hunter. This staff is necessary to open the door mentioned in the title of this chapter. Getting this item is very simple - defeat and search the enemies encountered in this location.
A problem may occur when you try to solve the puzzle presented above. There are four symbols on the shields:
-  - Moon
-  - Ngati
-  - Hands
-  - Rain
Rotate the dial and press the symbols by using dialog options. You can only press a symbol that is currently on the top of the dial. Open the door by pressing the symbols in the following order: Ngtai, Moon, Rain, Hands. This unlocks the entrance. You can now proceed to another part of the location.
Note - Rod of the Deep Hunter is an interesting weapon for a Wizard so don't forget to put it back into your inventory once you open the door. This two-handed staff deals 22-36 damage and has additional effects: +30% Damage, +8 Accuracy, +2 Penetration, -1 Deflection and +5% Recovery Time for 45 seconds per hit.