In Hogwarts Legacy, once you have completed The Caretaker’s Lunar Lament quest, you can begin using the Alohomora spell to unlock Level I doors and thus reach previously inaccessible areas of Hogwarts School of Witchcraft and Wizardry . One such area is the Long Gallery which, as you might guess from the name, is a long hallway lined with paintings. One end of the long gallery is near the llama’s fireplace in the potions classroom, while the other end is near the llama’s fireplace in the bell tower courtyard. At the end of the bell tower courtyard, there’s an arithmancy puzzle door, and you’ll need to do a bit of math to open it.
Related: How to solve the steeple puzzle in Hogwarts Legacy
How to open the Long Gallery puzzle door
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See those creature icons around the door? These correspond, from left to right, to the numbers 0 through 9. So wherever you see one of these creature icons, it represents a number between 0 and 9. To unlock the bell tower puzzle door , you have to make all the numbers at the tips of the triangles on the gate add up to the numbers in the middle of the triangles. To do this, you must roll the triangles near the door until they show the icon of the creature that completes each equation.
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The upper triangle spider bed (8) + 12 + ? = 22, so the “?” must be 2, which is represented by the dragon creature icon. So throw the “?” triangle to the left of the door until it shows a dragon creature icon.
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The bottom triangle indicates squid (7) + unicorn (1) + ?? = 9, so the “??” It must be another unicorn. Find it “??” triangle to the right of the door, next to the stuffed troll, and rotate it until it shows the icon of a unicorn creature. The door will now open and you can get loot, including the Portrait of the Gorgon and Conjuration of Ruins field guide page.
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