These are rather unusual doors that are quite common around Hogwarts. I think the official name for them are arithmancy rooms or arithmancy doors, as this is the class that this is based around. These are doors that have a black chalkboard on the door itself with an arch around the frame that contains several different animals or creatures.
When you interact with the door, the black chalkboard will change to reveal a puzzle. There are two math based puzzles to solve where each will have a missing piece represented with a single question mark ? and a double question mark ??. Solving these can be super confusing if you have not yet found the cipher. Since the game’s story doesn’t lead you to it, here is everything you need to know about getting through these math-based creature puzzle doors in Hogwarts Legacy.
What Numbers Do Each of the Animals Represent
The method behind solving the puzzle for these doors might be clear for many people but the tricky part is figuring out what number each of the animals actually represents. The solution lies in the Library Annex of Hogwarts Castle. If you make your way to the Divination classroom floo point, you will see a nearby doorway that leads up onto some wooden beams. Go down here and take the first right and you will find one of these metal doors with the animals around the frame. Inside a blue box nearby is the cipher to solve the riddle.
There is no way to know fore sure whether the cipher will be the same for all players. I would assume it is but in any event that this is not the case, here is a video guide that will show you where to find the arithmancy cipher that will teach you how to unlock all of these doors.
Examples For Solving the Math Blackboard Puzzle Doors
I will give a few examples below on how to solve these. I am pretty sure the actual math puzzle that appears on the chalkboard is randomized so there is no point in listing the solution to them all.
This door contains a lizard and a crab at the top with 15 being the goal number. We know that the crab = 5 and the lizard = 6 so the answer is 15 – 5 – 6 = 4. Check the cipher to find that the owl is number four. This means that the first question mark should be the picture of the owl.
The second box contains a 13 and that porg looking creature, which we know represents 0. The goal number is 18 so the answer here is 18-13 = 5. The cipher says that 5 is the crab. This means the double question mark should be the crab. Once both of these are set, return to the door and attempt to open it. The door will unlock for you.
