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- Can wizards create their own spells? 15 answers
Harry Potter and the Deathly Hollows:
"He lost his hood during the chase. Sectumsempra was always a specialty of Snape's. I wish I could say I'd paid him back in kind, but it was all I could do to keep George on the broom after he was injured, he was losing so much blood."
I always thought that Snape discovered/created this spell. The spell was handwritten in the Half Blood Prince's textbook. I also thought I remembered reading it somewhere.
Also in the movie Snape criticizes Harry when he tries to use it against Snape and tells Harry, "You dare try to use my own spell against me?" This implies it's Snape's spell.
But the passage above implies that it was a prefered spell of Snape's as opposed to something he created.
Was this a generally known spell that Snape used, or was it something that he created?