Deeproot Depths is a location in Elden Ring, situated underground. You can access this region in two ways: by resting in a coffin after defeating the Valiant Gargoyle in the Siofra Aqueduct or through a hidden passage near the Frenzied Flame Proscription grace in the Subterranean Shunning-Grounds. After accessing the zone and exploring the Root-Facing Cliffs for a bit, you'll find yourself at the Great Waterfall Crest site of grace. Nearby there's going to be a secret cave, with quite a few useful items and a powerful incantation.
After killing all the Ant monsters in the area and exploring the gigantic roots & branches you might have noticed a peculiar orange/white shine on a body on a nearby ledge which looks connected to a cave system. The item in question is the Elden Stars incantation, and exploring the cave will give you a decent amount of runes, as well as Somber and Regular Smithing stones.
The cave entrance is actually quite well hidden, and most people miss it. In order to access it, start at the Great Waterfall Crest grace, head west until you encounter some roots. Look northwest to spot a root leading up to a cave that looks quite dark. Follow the root into the cave and battle through the packs of Giant Ants. At the end of the cave, you'll find Elden Stars on a body near the exit. Afterwards, you can continue to explore the area further in order to reach the Deeproot Depths grace.
