Find Cave F
Look for a small ground opening in the northeastern rocky area with a rope leading down. This is Cave F / Solafite Cave, not the cabin entrance used for another Artifact piece.
Bring the Rebreather, air tanks, lighting, medicine and food.
Follow the main route
- Descend the rope and follow the stream towards a small waterfall.
- Near the drop, use the descending passage on the right. Collect the visible air tank and dive.
- After surfacing, take the left fork; the right side is a dead end.
- The boarded branch contains the weapon-plating blueprint and a deeper Artifact route. For the Pickaxe, continue along the unblocked left main passage.
- Slide into the next water area. An air tank can be collected ahead before diving through the onward tunnel.
- After surfacing, continue through another water passage.
- At the two paths in the final dry section, go left to the Pickaxe embedded in the Solafite deposit.
Collect it and confirm Pickaxe in the inventory. It lets you mine the ore needed for Ancient Armor plating.
Leave after checking your inventory
Continue forwards to climb a rope. The following drop cannot be reversed, so check the pickup first. Find the next rope ahead, climb it and follow the passage out.
The boarded side branch’s weapon-plating blueprint is not the Armor Plater blueprint used at the Golden Door.