In Hogwarts Legacy, the Arithmancy classroom is on the upper level of the Library Annex and is locked behind a puzzle door. Once you enter the Arithmancy classroom, you’ll discover two more puzzle doors next to each other, so it’s time to practice some more arithmancy (i.e. say math magic) to open them for loot.
Related: How to complete Herodian Hall in Hogwarts Legacy
How to Open the Arithmancy Classroom Doors in the Library Annex
To enter the Arithmancy classroom in the first place, you will have had to solve the Divination classroom door puzzle, so you know how these puzzles work. The creature icons around the door correspond, from left to right, to the numbers 0-9, and you need to roll the side triangles so that the numbers on the ends of the door’s triangles add to the numbers on the inside. inside the door triangles. Triangles. doors
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The top triangle on the left door indicates quintaped (5) + salamander (6) + ? = 15, so the missing creature icon should be an owl (4), so roll the triangle to the left of the door until it shows an owl. The bottom triangle indicates 13 + demiguise(0) + ?? = 18, so the missing icon must be a quintap (5), so rotate the triangle to the right of the door until it shows a quintap. You can now open the door and loot the study, where you will find two chests, one of which contains the Trees Conjuration exploration collectible.
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The upper triangle on the door to the right in the Arithmancy classroom reads 6 + quintaped (5) + ? = 17, so the missing icon should be a salamander (6), so rotate the triangle to the left of the door until it shows a salamander. The bottom triangle indicates squid(7) + 0 + ?? = 8, so the missing icon must be the unicorn (1), so rotate the triangle to the right of the door until it shows a unicorn. You can now open the door and search chests for loot, including the Conjuring of Medium Floor Coverings exploration collectible.
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