Grounded contains a number of different items that don’t serve a clear purpose. For instance, the Mossy Key is described as “A thick and chunky moss-covered key,” and it’s clearly meant for some purpose. So what does the Mossy Key do? Here’s more information about what this key does and where you can find it.
What Does the Mossy Key Do in Grounded?
The Mossy Key is an important item in Grounded that unlocks a treasure chest at the entrance of the Pond Depths. The purpose of the key is to open the treasure chest containing the Sunken Outpost BURG.L Chip. It is located within a long underwater tunnel.
In order to get to the key, make sure to equip your Bubble Helmet and Fin Flops. The Merteen Mutation will also be very helpful underwater. In addition to the mutation, you might want to have Liquid Gills and Fluid Flippers in your backpack. With all that taken care of and with your light source in hand, you are ready to go.
From the underwater base, drop down into the water and look for a cave tunnel with a lot of algae surrounding its entrance, which should be located under some sort of water pump. Watch out for the diving bell spiders since they might be a problem. However, note that killing spiders resupplies your air. Swing through the long tunnel, and make sure to get some air from the leak coming out of a cable that you will find on the way. The Mossy Key should be down there, near the cable. Just swim close to it and grab it.
Now, head back to the underwater base for some air. Keep swimming past it to where the T-Rex is located. Just swim towards lights, going in the opposite direction of where Mossy Key was located. The huge treasure chest should be on the bottom of that area, next to a root. Now you can open the chest and get the Sunken Outpost BURG.L Chip in it.
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