|The River Pass
Just before the bridge where you meet Brok for the first time (or where you find a Mystic Gateway) you’ll see a chain that you can drop to access the area below. Follow this path to the end to find the first Mask.
Head to where Brok’s Shop is, just past the large bridge and head to where the tress are to the right of him. There’s a small ledge you can drop down to find the corpse with the second Mask.
After you solve the puzzle of the spiked ceiling, climb up the ledge and as you approach the exit, there’s a corpse with the Mask to your right.
From where you found Mask #3, head out of the cave and after you regain control, continue walking toward the wall in front, the Mask is sitting near a corpse.
Once you open the runic door via the sand bowl, proceed into the cave beyond. You’ll reach a fork, turn left and climb the ledge to find a pool with the Mask sitting there.
Head to the deserted village and look for the only burning house in the area. Search around the back of the house to find another corpse with a Mask.
When you leave the Witch’s House for the first time and enter the main room where the Nightmares are, you can drop down a ledge to the left. In this area is a cart you can push into the water, creating a path to the Mask.
When you return to the Witch’s Cave later in your journey, you’ll have to climb up the well to access her Sanctuary. From the exit of the well, head down the path and you’ll find the corpse at the end with the Mask.
When you return to the Witch’s Cave to deliver Mimir’s head to the Witch, you’ll find yourself in the sanctuary in front of the turtle. There’s a chain here that you can climb, defeat the Draugrs and then check the corpse to find the final Mask.