The deep sea is much darker than previous areas. Rely on the bioluminescence of the creatures and the subtle glow of ancient structures to guide your way. You'll encounter unique deep-sea fish, some of which are quite large and majestic. Don't be afraid to approach them.
Look for glowing pathways on the seafloor or along the trench walls. These often lead to the next objective or a hidden collectible. The atmosphere here is designed to be both beautiful and slightly unsettling, emphasizing the vastness of the ocean.