There are tons of puzzles and features to discover in Hogwarts Legacy, all of which are included in the Challenges portion of your menu. Hogwarts Secrets are puzzles you can solve around the castle that lead to Legendary Chests, Collection Chests, and appearance rewards. One particular Hogwarts Secret consists of the curious metal door across from the Headmaster's Office. This mysterious door is in need of a key, and here is where you can find one.
How to open the door opposite of the Headmaster's Office in Hogwarts Legacy
You'll find the metal key door you'll need to ascend up the staircases toward the Headmaster's Office. Take the Trophy Room Floo, walk through the room and to the right where there is a gated staircase. Go through the gate and keep ascending the staircases until you reach the hallway of the Headmaster's Office entrance. The locked metal door will be to the right at the end of the hall.
To unlock the door, you'll need a special key locked away in a room within the Headmaster's Office. This means you'll need to have Niamh's Trial done to gain access to the office and have a level three Alohomora, which you can get by locating Demiguise Moons. Here's where to find the key:
Head up into the Headmaster's Office and locate the locked door beside a telescope on the left side of the room. This will be a level two lock. This leads outside to another staircase leading up to a level three lock door. You can unlock this if you have all Alohomora upgrades.
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Once you unlock this door, you will find a little library. To the right of the fireplace, you'll notice a desk of sorts, and at the very edge is a key that you can interact with. Pressing X or Square will allow you to collect the key. This is the key that you need to unlock the metal door.
Exit through the Headmaster's Office and down the spiral staircase to the entrance hallway. Head to the door, and you'll be able to open it using the key. Inside you'll see a Legendary Chest at the bottom of the stairs. You can go up the stairs to find a Field Guide and two Collector's Chests as well.
Keep an eye out for more secrets and puzzles around Hogwarts Castle and grounds. There are plenty to solve, and all usually have a worthwhile prize and reward.
Looking for more Pro Game Guides Hogwarts Legacy content? Check out our guides on All Daedalian Key locations in Hogwarts Legacy or What to do at the map wall in the South Wing in Hogwarts Legacy!
Abby Smith is a super nerd and video game fanatic and grew up playing games on a variety of platforms. She likes to spend her free time binge-watching Netflix, reading all genres of novels, and playing all the best new video games. She is currently a full-time Staff Writer for Pro Game Guides, and as an alumni from Full Sail University, also enjoys dabbling in creative writing such as short stories, scripts, and comics on the side.