Geothermal Valley - Pit of Judgment Challenge Tomb (Part 4)

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Swim back across the pool...

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...and enter the codex room.

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Here you'll find 2 clumps of mushrooms, a container of cloth, a box of supplies, and the second document (18/33) in The Pit of Judgment series, titled The Overseer (Greek). Of course there's also the codex itself, which unlocks the Geologist skill (plus XP and 10,000 Expedition Credits).

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This skill allows you to find chromite ore, which can be used for certain advanced weapon upgrades and outfits that involve armor plating. Now whenever you mine magnesite, there's a chance you'll also get some chromite. There's a vein of ore on one side of the treasure room where you can try this now, plus 2 lumps of ore in the doorway leading outside. Chromite is listed under Exotic Resources in the Resources section of your Map/Inventory screen.

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Swim back across the pool toward the entrance.

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To bypass the slippery slope where you came in, climb the rough wall on the left to the ledge above.

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Latch onto the next section of climbable wall and climb up and to the right. Jump across to the right and continue climbing onto the ledge above.

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Go through the low tunnel with the dangling roots.

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Return across the fallen tree.

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Then jump across the chasm to the climbing wall on the right. Climb to the left and upward until you reach a pair of thin, stone handholds.

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Continue climbing around to the left until you can drop down into the tunnel that leads back to the Hidden Ravine Base Camp.

[Part 3 | Return to the Challenge Tomb Walkthrough]