At Hogwarts Legacy, the Great Hall is one of six areas of Hogwarts School of Witchcraft and Wizardry. It overlooks the lake on the southwest side of the school and has three chimney flames: one in the boathouse on the lake, one in the great hall, and one in the courtyard of the viaduct. The Great Hall is also the location of one of the school’s Arithmancy Gates, which must be unlocked using the ancient magical art of Arithmancy (which is basically mathematical magic). These door puzzles can be confusing at first, but with a little help, you can make the solutions add up.
Related: All Demiguise statue locations at Hogwarts in Hogwarts Legacy
How to open the puzzle door in the Great Hall of Hogwarts Legacy
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The Great Hall puzzle door is located at the end of a hallway leading to the northeast corner of the Great Hall. Head east from the Great Hall Floo Flame, then turn left. He “?” And “??” the triangles are also in this same corridor.
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To unlock the door you need to roll the triangles so that they display the creature icon which represents the number that will cause the tips of the triangles to add up to the numbers in the middle of the triangles. The creature icons are numbered 0-9, left to right, so the semi-guide is 0 and the snakes are 9. The top triangle says snakes (9) + 7 + ? = 24. This means that the “?” should be 8, which is represented by the spider icon, so discard the “?” triangle until it shows a spider.
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The bottom triangle indicates 11 + demiguise(0) + ?? = 14. This means that the “??” should be 3, which is represented by the hydra, so roll the “??” triangle until it shows a hydra. You can now open the door and loot the chests inside, one of which contains the Scout Conjuration Crests collectible.
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