In Destiny: The Taken King's Fall Raid, there are numerous Secret Chest location. All of them are not easily available, Bungie made sure that they are very well hidden so that players were forced to use teamwork and bit of their brain to get access to them. This Destiny: The Taken King provides detail on all King Fall Raid's Secret Chest Location. Please note, the rewards for discovering each chest differs, they are randomized and possibilities is there that the rewards may contain exotic weapons.
Shortly after the hive ship jumping puzzle you will reach a platform that requires two fire team members to stand on activators. Instead of riding the ship through the doorway, jump to the wall on the left hand side. Scale the wall and jump into the hole. Once you reach the other side you can open the chest and then jump down and open the portals from the opposite side and the remaining two members of the fire team can then get the chest.
Inside gorgroths maze, you will find FOUR doors with flower covered pressure plates. One of them is hidden behind a large door that requires you to jump through a very small hole above it. When you jump onto the pressure plates they make lots of loud noise. You will glow when you jump on them in the right order. A large door will open and a chest is inside.
During the piston jumping puzzle, once you reach the very first platform, open your ghost and check out in the open for the invisible platforms. Scale the platforms and then jump from the pillar to the wall and enter into the room with the chest. Use the invisible platforms to scale back down.
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