Like the sorting hat you can do the patronus once a student is able enough to be able to get her/his Patronus
I like being able to choose our own for profiling purposes. To me it makes it more meaningful and unique to each person. After all, who knows which patronus your character should have better than you?
I think you should only be able to choose your patronus at a specific age too
It would be fun if you can set your patronus on your profile information. You can set it once.
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