How to solve the Central Hall door puzzle in the Library Annex in Hogwarts Legacy
The Magical Paintings Conjuration lies beyond this door.
In Hogwarts Legacy, one of the first door puzzles you’re likely to come across is in the Central Hall of the Library Annex of the school. You go there by using a Floo Flame for the first time at the end of the Welcome to Hogwarts quest. You now have a choice between Defence Against the Dark Arts Class and Charms Class, but you can also do a bit of exploring, puzzle-solving, and chest looting first.
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How to open the Central Hall puzzle door in Hogwarts Legacy
After speaking to Professor Weasley and Professor Fig in the Central Hall, go down the staircase to the south, and turn right. Here you’ll find a locked door surrounded by an archway marked with symbols of various creatures. Examine the door itself, and you’ll see two triangles with creature symbols, numbers, and question marks on them. Top unlock the door, you need to figure out which creatures should be in the spaces with question marks, and then roll the nearby triangles until they show the correct creatures.
Going left to right, the creatures represent numbers from 0 to 9, and the three numbers on the points of each triangle must add up to the number in the middle of the triangle. So, the top triangle is 11 + 2 + ? = 21, so the missing creature must be 8, which is the spider. So, roll the triangle next to the door until it shows a spider.
Next, the bottom triangle is 5 + 9 + ?? = 17, so the missing creature must be 3, which is the hydra. So, go upstairs and roll the triangle directly above the locked door until it shows a hydra. Now, when you go back down and interact with the door, it should open, and you can go inside and loot the two chests, one of which contains the Magical Paintings Conjuration exploration collectible.