Destiny: The Taken King has its share of secrets, with the Dreadnaught containing nine hidden chests that require special keys to open. In order to obtain the aforementioned keys, you’ll need to first get a “Wormfeeder Rune.” You’ll want to spawn into the Dreadnaught where you will soon come across an ogre named Blahgrish (which you can summon using a Wormsinger Rune or, more likely, another player will have summoned it as it’s very common right now). Killing it drops the rune you’re searching for.
The rune comes with a challenge for you: get 50 kills on the Dreadnaught. Watch out though, because deaths will reset your progress. Once you complete this challenge, the rune will turn into one of nine possible keys to be used at the appropriate chest.
The Akka Chest can be found in the Court of Oryx, on the right-hand side of a platform.
The Eir Chest is in the Hull Breach area. Head through the wall past some Cabal crates and continue going through the cave passage.
The Gnashing Teeth Chest is found underneath the Court of Oryx platform.
The Maggots Chest is in the connection between the Mausoleum and the Hull Breach.
The Spawn Chest – go to the Mausoleum and look to the right, where it appears like there is no walkway for you to jump on to reach a distant opening. Use Ghost to show the path to take.
The Ur Chest can be found on the lowest level of the Dreadnaught patrol, right after spawning in.
The Wyrding Chest can be found by heading to the Mausoleum and taking the door to the right and continuing on that path.
The Xol Chest requires you to spawn in the Hull Breach area of the Dreadnaught and head to the room on your right and continue on that path.
The Yuul Chest requires you to get to a walkway to the right of the Court of Oryx platform.
Safe travels, guardians.