Harry Potter: 10 Hardest Spells To Master

With an entire society mired in secrecy, and huge systems and potential punishments in place to ensure they are never exposed, making someone forget a memory could come in very handy for witches and wizards.

We have seen obliviation used several times in the Harry Potter world, most notably when Hermione used the spell to make her parents forget her, and at the end of Fantastic Beasts where the spell was somehow combined with the rain to make the people of New York forget the huge Obscurial that terrorised the city.

While this may be a relatively simple spell to perform, it is very difficult to get right, with terrible consequences if it goes wrong. When removing someone's memory, the witch or wizard has to be incredibly careful in choosing what exactly they are erasing. If the spell backfires, like it did with Gilderoy Lockhart in the Chamber of Secrets, the subject can be left with lasting, incurable amnesia.

Though the fault here was Ron's broken wand, it does go to show what can happen if it goes wrong, regardless of the reason. In the books, Barty Crouch Sr used the charm on Bertha Jorkins, but went too far and permanently damaged her memory.