How to access the Temple of Ceres Hidden Ones Bureau and collect the Codex Page and Hidden Ones Leggings. You can find this one in eastern Glowecestrescire, near the Forest of Denn.
Enter the Temple by breaking open the crates on the right side and sliding through the gap (might take a few attempts). From here you need to navigate through the fume soaked rooms to a hole you can drop down into to get to the second level. Use your torch to dispense the fumes as you go.
On the lower level, move through the passages until you find a breakable wall. Either use an explosive arrow or backtrack for an oil jar to break through to the main chamber where you'll find the Codex Page and Hidden Ones Leggings. This will complete the Hidden Ones Armor set
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