Dredge Stone Tiles

There are 3 Stone Tiles in Devil's Backbone. All of them are under water and are marked as places with treasures. But unlike the usual visual effects, you will see a golden glow at the right points, where the tiles lie on the bottom. The Devil's Backbone is not that big, so it makes no sense to indicate the location of all three tiles. Collect them, it will not be superfluous to use explosives to avoid the fish.

When you get all three tiles, swim to Little Salt and talk to the merchant. He will say that he has another part. If all 3 tiles were brought to him, then he will put them together with his own and you will receive an ancient tablet. Swim to the Ancient Lighthouse on the eastern part of Devil's Backbone (there is a black dot on the map). Climb the lighthouse, place the tablet and you can search it. Get treasure and ship lamp (25m range, +3500 lm).