I thought Voldemort invented Avada Kedavra?
Is Rowling retconning here?
No he didn't invent it, where in the world did you get that idea from?share
I read it somewhere.
What was the name of the slicing curse that Snape invented when he was high school age?
That may be what you're thinking of.
Sectumsempra. Yes, it may have been that, and then I deduced that other wizards have invented other spells, too.
Then again, it would be obvious that a spell to simply kill would be one of the oldest in the WW.