Below is a walkthrough on the Level 5 Deep Trouble side quest in Horizon Forbidden West. To obtain this side quest, speak with Korvend at the Crimson Narrows.
Find the Missing Miners
Head into the mine at the Crimson Narrows. Crouch under a small opening to the left then dive down into the flooded mine. Once you reach the other side, head right to find an underwater path that will lead you to the miners.
Talk to the Miners
Speak with the miners to learn about the situation.
Find the Blockage
To drain the mine, you must first find the blockage. Jump into the water northwest of the miners and dive underwater. Follow the path. Boost through the water to get to the current to find a ladder that you can climb up on the other side.
Go to the Mine Cart
Head to the northwestern side of the room to climb onto a wooden platform. From there, jump up to a ladder and follow the path. When you reach the room with the Burrowers, dive underwater to swim under them. Continue following the path underwater until you find a rock wall you can scale. Do so then defeat the Burrowers. Follow the mine cart tracks to a climbable wall. Climb up it then crouch through the small pathway. When you emerge into the open room, scan the crane jutting out over the water. Next, pull the crane towards you then jump onto it to reach the upper track with the mine cart.
Detonate the Explosives
Interact with the mine cart to detonate the explosives.
Return to the Miners
After the mine clears, machines will spawn. Defeat them then return to the miners. Along the way, you’ll have to pull out some crates blocking the way. When you reach the miners, speak with them.
Return to Korvend
Continue backtracking towards the entrance of the mine then speak with Korvend to complete the quest.
Rewards
- 1250 XP
- 2 Skill Points
- 1 Oseram Artificer