Much like the base version of Horizon Forbidden West, The Burning Shores DLC features special puzzles known as Relic Ruins. Well, technically, it only features one of them, but solving the Murmuring Hollow Relic Ruins can be every bit as enjoyable as any of the rest. As usual, doing so will reward players with a special ornament for their troubles, which they'll then be able to take to Stemmur in Hidden Ember for a special light display.
Although it's possible to reach the Murmuring Hollow Relic Ruins almost immediately after starting the Burning Shores DLC, players won't actually be able to solve the puzzle until after they have finished the To the Burning Shores main story quest. In addition to an Ornament, completing the Murmuring Hollow Relic Ruins will unlock a special side quest that rewards players with a Legendary weapon.
How to Get the Murmuring Hollow Relic Ruins Door Code
The Murmuring Hollow Relic Ruins are slap-bang in the middle of the Burning Shores map just northeast of Fleet's End. Players should approach while flying on Aloy's Sunwing and look for a rooftop area with a perch and a blue metal clamp. Pressing the Triangle button while near this clamp will lead to the Sunwing tearing it open, granting access to the room below. Players can then climb up the nearby shaft and scan the purple datapoint, which will reveal that the Murmuring Hollow Relic Ruins door code is 1315.
How to Get to the Ornament
Now that they have the code, players should head back outside and look for the nearby campfire, which also serves as one of Horizon Forbidden West's fast travel points. Near the cliff behind the fire is a metal bar from which Aloy can repel, which will lead players down to an underground area with some train cars. Here, players should pry open the door of the train on the left by holding R2 and then pull the lever inside by pressing Triangle.
Pulling this lever will cause the train to move, allowing players to remove the energy cell from the side and take it through to the area on the other side. Next, players should put the energy cell into the slot on the side of the other train car opposite the key module door to provide power, at which point, they can pry open the door and pull the lever inside to cause the train car to roll backward. It almost falls off a cliff, but Aloy manages to survive.
From here, it's a simple case of heading over to the door to the right and then inputting the four-digit code (1315). On the other side of this door, Horizon Forbidden West players will find the Kyle's Last Ball Ornament, which appears to be Oktoberfest-themed. Picking the Ornament up will technically mark the end of the Murmuring Hollow Relic Ruins, but there's still a bit of work to be done here before heading back up to the surface.
If players go back and grab the energy cell from the train car they just moved, they can use it to open the door in the Ornament room. On the other side, they'll find an Auxiliary Key Module, which can be used to open the nearby door. This will reunite Aloy with Gildun and trigger the beginning of the A Friend in the Dark side quest. It's a relatively simple one and will reward players with a Legendary Spike Thrower called the Last Argument.
Horizon Forbidden West is available now on PS4 and PS5.