It is pertinent to mention that Harry only knew Sectumsempra was for enemies and that to him, was reason enough to use it in his duel with Draco Malfoy that took place in the boys' bathroom.
Professor McGonagall considered Harry to be very lucky not to have been expelled for such an act and full-heartedly supported the detentions, while Pansy Parkinson wasted no time in vilifying Harry far and wide; Ginny Weasley, however, stood up for Harry's usage of the curse, as it saved him from being struck by ...
There is likely a good reason that the Sectumsempra is not an unforgivable curse. It's mostly because Sectumsempra is Snape's personal curse that he created. It is not a widely known or used spell, and it is one that he kept secret — which means it can't be added to the list since no one really knows about it.
The curse was invented by Severus Snape during his time as a student at Hogwarts, in retaliation against his enemies. He recorded it in his textbook and used it enough to make Remus Lupin recognise it as one of his signature spells.
Vulnera Sanentur was the song-like incantation of a healing spell and counter-curse to the Sectumsempra Spell, which was invented by Severus Snape. While sectumsempra was invented by Snape, Vulnera Sanentur is often mistaken to be invented by him as well.
Why Sectumsempra Isn't an UNFORGIVABLE Curse - Harry Potter Theory
How did Snape cure Draco?
It's implied that Septum Sempra is Snape's own creation, that he used a specific counter-curse to heal Draco, and that the spell isn't designed to be instantly fatal, but to inflict a gruesome, but relatively slow death if left untreated. It's likely Snape is the only person who knows said counter-curse.
Harry yells “Sectumsempra,” the hex scribbled in the margins of the Half-Blood Prince's book. Blood spurts from Draco's face and chest, and Myrtle beings screaming. Snape bursts into the room and heals Draco's wounds almost immediately. Snape hurries Draco to the hospital wing, commanding Harry to wait behind.
Harry Potter's use on Draco Malfoy in the Duelling Club. The Tickling Charm (Rictusempra), also known as the Rictusempra Charm, is a spell that causes a victim to buckle with laughter. It also has at least two other side effects on the victim. It is usually used as a diversionary tactic in duels.
The injury was caused by Snape's Sectumsempra spell in order to stop the Death Eaters from hurting George (who he thought was Harry) and Lupin, but missed and hit George. Hermione and Kingsley then arrived, both unharmed, followed by Arthur and Fred Weasley, both concerned for George.
What is the difference between diffindo and sectumsempra? Diffindo and Sectumsempra have similar magical effects, but Sectumsempra is dark magic and therefore difficult to deflect.
In the final movie, Harry Potter and the Deathly Hallows pt. 2, Molly first hits Bella with a spell that freezes her, most likely Petrificus Totalus. Then, she launches another one that shatters her entire body into pieces, which could be expelliarmus, bombarda, stupefy, or any spell that can produce such an effect.
Although it is not confirmed to have been the Killing Curse, it is highly likely that Ron attempted to kill Voldemort's snake, and last Horcrux, Nagini, with Avada Kedavra. This is because, in the movies, Ron can be seen firing out a green spell at the snake, and it looks just like the Killing Curse.
In Harry Potter and the Deathly Hallows: Part 2 and subsequent video game adaptations, this event takes place in the Boathouse instead of the Shrieking Shack. Instead of lowering the protective orb over Snape, Voldemort instead slashed his throat, and then had Nagini attack the weakened Snape.
Family. Snape's family background is mostly shown in flashbacks during the course of the last three novels. Snape was born to Eileen Prince, a witch, and Tobias Snape, a Muggle, making him a half-blood (hence the name, "Half-Blood Prince").
Harry describes Umbridge to Sirius Black, saying that she's vile enough to be a Death Eater, despite not being one. Umbridge is also depicted to be a prejudiced person, despising half-breeds and Muggle-born witches and wizards to the point of firing Hagrid due to his half-giant birth status.
Salvio Hexia is a defensive spell which presumably deflects hexes from the area. The caster must move their wand in a downwards direction in the opposite direction of their outward hand. The spell must be cast multiple times around an area to be successfully set to defend.
The charm was invented by Severus Snape and recorded during his time as a student at Hogwarts School of Witchcraft and Wizardry, meaning it would have been created sometime between 1971 and 1978.
J.K. Rowling says Draco doesn't have a patronus because he never learned the spell but I think it's because he doesn't have any powerful happy memories to use. He has tons of happy memories... He had an amazing childhood. However, she also said Snape was the only Death Eater who could produce a Patronus.
The Malfoys are related to the Black family through Narcissa (a first cousin of Sirius Black, Harry's godfather), which makes Draco a nephew of both Bellatrix Lestrange and Andromeda Tonks.
Although healing magic could usually heal injuries without scarring, with dittany being one of the more effective, injuries caused by Dark Magic usually left scars that could not be healed, as Severus Snape expressed possibility that Draco Malfoy may have had some scars from the Sectumsempra curse, and Bill's scars ...
