Geothermal Valley - Pit of Judgment Challenge Tomb (Part 2)

Swim across the pool to the north side.

From here you can glimpse the codex behind a wooden barrier. Dig up another survival cache (13/20) buried off to the left.

Now tackle the puzzle. Turn around and scope out the two long mine cart tracks. The tracks on the left are blocked by debris, so run up the ones on the right.

At the top, on the left, just before the octagonal platform with the mine cart, is a box containing a relic (8/13), a Rope Ring from the Time of Adaptation set.

The mine cart moves but a wooden bumper prevents you from pushing it along the track. Use your axe as a handle to turn the wheel, rotating the platform beneath the cart 180 degrees.

Now you can push the cart forward along the track until gravity takes over...

...and the cart plummets down the slope and crashes into the wooden barrier below. One down; one to go!

Return to the top of the track. There's magnesite embedded in the wall ahead on the left. In the dark alcove at the back, you'll find a document (17/33), Unrepentant from the Pit of Judgment series (Greek). Follow the tunnel to the right...

...and jump across the pit. In this dead-end tunnel, there's a container with cloth and 2 Byzantine coins, a lump of magnesite (ahead on the right, not shown)...

...and the Archivist Map (6/9) for this area, which reveals the location of any unfound documents and relics on your map.

Return to the movable platform where the mine cart was and continue straight through to the ledge with the rope-wrapped post. Shoot an arrow into the beam on the other side of the cavern to create a rope line. Then slide down to the base of the wooden structure supporting the second set of tracks.