Located in the Tower Knight Archstone and found by weaving through tight, dark corridors, the mysterious door welcomes players with a single message: “It appears to be locked.” It does not provide any further information on how to get through to the other side.
Fortunately, streamer and speedrunner Distortion2 has now unlocked the puzzling portal, solving the mystery once and for all. Much to our surprise, one of the new additions to the remake—the Ceramic Coin—was the key all along. Ceramic Coins are well hidden and are often under breakable boxes but can only be found with either Pure White or Pure Black tendency.
Distortion2 cleverly noticed that the design on these Ceramic Coins happened to match the design on the mystery door and after trading thirty of these to Sparkly the Crow, an item trader in Shrine of Storms, they received a “Rusty Key”.
We solved the mystery of the hidden door! Thanks for making such a great secret to get all the community involved @bluepointgames Was awesome looking for the coins in SOTC Remake and again in Demon's Souls Remake 😀 pic.twitter.com/gNpozqEztJ
So, what sort of glorious treasures lie beyond the mysteriously locked door? Not a whole lot, as it turns out. Behind the door is a reasonably small terrace with the body of a dead knight. By looting the body, the player receives some pretty sweet gear, however. Namely, the Penetrator armour set and a sword, styled after the Main Plaza boss of the same name.
Some more pictures of the new Penetrator Armor set from behind the hidden door! Looks really nice with proper lighting 😀 pic.twitter.com/AfiVSGTN4G