In Hogwarts Legacy, one of the first door puzzles you’ll likely come across is in the center hall of the school library annex. You go there using a Floo Llama for the first time at the end of the Welcome to Hogwarts quest. You can now choose between Defense Against Dark Arts class and Enchantment class, but you can also explore a bit, solve puzzles, and loot chests first.
Related: How to Solve the Bridge Fire Puzzle in Hogwarts Legacy
How to open the Central Hall puzzle door in Hogwarts Legacy
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After speaking with Professor Weasley and Professor Fig in the central hall, go down the stairs to the south and turn right. Here you will find a locked door surrounded by an archway marked with symbols of various creatures. Examine the door and you’ll see two triangles with creature symbols, numbers, and question marks on them. Open the top door, you need to know which creatures should be on the spaces with question marks, then rotate the nearby triangles until they show the correct creatures.
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Going from left to right, the creatures represent numbers from 0 to 9, and the three numbers at the points of each triangle must add to the number in the middle of the triangle. So the upper triangle is 11 + 2 +? = 21, so the missing creature must be 8, which is the spider. Then roll the triangle next to the door until it shows a spider.
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So the lower triangle is 5 + 9 + ?? = 17, so the missing creature must be 3, which is the Hydra. So, go upstairs and rotate 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 in and loot the two chests, one of which contains the Magical Paintings Conjuration exploration collectible.
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