This guide, along with the annotated level maps linked below, should help find any explorer satchels you missed. Finding an Explorer Satchel reveals the location of various Survival Caches, Strongboxes, Crypts, and minor caves on your in-game map. The Survival Caches these satchels reveal are detailed separately. If you are playing through this level for the first time, you may want to follow the main walkthrough instead.
EXPLORER SATCHEL 1
The first satchel is on the way to the House of the Afflicted Challenge Tomb. As you cross the broken wooden walkway leading from the village to the tomb, you'll use a rope arrow to swing across a wide gap. The satchel is just after this on the left. Check the map and walkthrough for details. (Click screenshot to enlarge.)
EXPLORER SATCHEL 2
This satchel is in the House of the Afflicted Challenge Tomb. On your first visit, follow the walkthrough. To retrieve the satchel later on, return to the Infirmary Base Camp and re-enter the puzzle room. Hop into the shallow pool on the right (northwest) side of the room and swim through an underwater opening into the next room. (screenshot) The satchel is here. (Click screenshot to enlarge.)
EXPLORER SATCHEL 3
This satchel is sitting on a stone ledge near the waterfall in the northwestern corner of the valley. To reach it, follow the path to the Architect's Crypt as detailed in the walkthrough. (Click screenshot to enlarge.)
EXPLORER SATCHEL 4
The fourth satchel is sitting in an alcove just south of the Aqueduct Ruins Base Camp, which becomes accessible after the first combat section in the upper village. If you missed the satchel the first time through, just fast travel back to this camp to retrieve it. See the map and walkthrough for more info. (Click screenshot to enlarge.)
EXPLORER SATCHEL 5
The last satchel is in the tunnel leading to the Pit of Judgment Challenge Tomb. Again, follow the main walkthrough if it's your first time raiding the tomb. Otherwise, fast travel to the Hidden Ravine Base Camp. Grapple-swing across the deep pit northwest of the campsite, and you'll find the satchel just ahead on the right, near a small waterfall. (Click screenshot to enlarge.)
†UPDATE HISTORY: 6/11/16 - Page first posted online.
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