The Green Turtle Talisman is a bit of an ironic item. It increases your stamina regeneration, which is something everyone can agree is great. The area you find this talisman requires you to use a Stonesword Key. Remember that before making the journey. Here is where you find the Green Turtle Talisman in Elden Ring.
The talisman is found in the northern section of the map above Mistwood. You are looking for Summonwater Village. This area is filled with skeletons and is home to the Tibia Mariner boss. Be careful when traveling through this area and kill the boss first if you need. The boss is relatively easy to handle but will summon a large number of skeletons to help it in battle.
Go to the southeastern section of Summonwater Village. Here, you will find some turtles walking around near a staircase with a fog wall. Use a Stonesword Key on the imp statue next to the stairs to remove the fog wall. Below, you will find a room filled with turtles. Open the door on the far side of the room to uncover a chest. Inside the chest is the talisman.
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