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Archchancellor's study

The study while Weatherwax lived there.

My door is always open because then, when I'm bored, I can fire my crossbow right across the hall and into the target just above the Bursar's desk.

The Archchancellor's study is an office located in the Unseen University where the current Archchancellor resides. It reads "Archchancellor" on the door[1].

When Mustrum Ridcully came into possession of the office, he often left his door open so, when he was bored, he could shoot his crossbow into Dr. Dinwiddie's study[2].