Though Harry encountered many opportunities that deemed Avada Kedavra necessary, it remains as one of the Unforgivable Curses Harry Potter never cast. For one, he viewed the spell as an immoral practice commonly used by users of the Dark Arts.
Why doesn t Harry use Avada Kedavra on Bellatrix? Harry didn't use that spell because he cannot bring himself to kill anyone. He is not a killer.
The darkest of the Dark Arts, Harry Potter unforgivable curses are the Cruciatus Curse, the Imperius Curse, and the Killing Curse. Although the curses are highly illegal, Harry using Unforgivable Curses happened, but he uses them once he was thrust into the Second Wizarding War.
None of the good guys dare use the Killing Curse throughout the events of the movies and books, no matter how high the stakes and how difficult things are. But Ron Weasley is the exception, giving it a go in the Deathly Hallows: Part 2 movie when himself and Hermione look destined to die via Nagini.
McGonagall followed up Harry's action by using the Imperius Curse on Amycus before tying him up with a net, rendering him useless during the Battle of Hogwarts.
Draco Malfoy (Cruciatus and Imperius Curses)
Although the use of these curses is rightly unforgivable, it's important to note that Draco never used them for his own benefit. It was always the pressure from Lord Voldemort that forced Draco into his crimes.
Cruciatus Curse ('Crucio')
Repeated use of the Cruciatus Curse is torture and Bellatrix Lestrange subjected the Longbottoms to such extremes of pain that it sent them insane. 'Better dead than what happened to them,' was what Moody said of the Longbottoms' fate, and there's a sad ring of truth to that statement.
Malfoy spots Harry and casts a Cruciatus curse; Harry, defending himself, using the Half-Blood Prince's Sectumsempra spell without knowing its effects. To his horror, it gashes Draco's face and chest, spilling his blood everywhere. Moaning Myrtle flies off, screaming.
Avada Kedavra
Topping the list for the most powerful spells in the Harry Potter universe is no other than Avada Kedavra, Voldemort's favorite to instill his will and fear onto others. The spell itself is a play on Abra Kadabra and is easy to cast by just about anyone in the Wizarding World.
Cruciatus Curse ('Crucio')
Harry tried to use this spell himself. The first time was against Bellatrix after she had killed Sirius. His attempt was unsuccessful because, as Bellatrix mockingly explained: 'You need to really want to cause pain – to enjoy it – righteous anger won't hurt me for long…'
The author explicitly states that both women were fighting to kill, despite Molly refraining from casting the Unforgivable curse Avada Kedavra. The result of the duel actually comes about as a result of nothing more than spectacular accuracy on Weasley's part.
For example, despite being furious with Bellatrix Lestrange for her murder of his godfather in 1996, Harry Potter was only able to cause her a brief moment of pain with the Cruciatus Curse because he used it out of "righteous anger", though he was still able to knock her off of her feet with it.
During the duel, Bellatrix shot a Killing Curse at Ginny. Bellatrix's curse narrowly missed Ginny, sparing her death by mere inches.
5 Bellatrix Lestrange: The Cruciatus Curse.
Someone as shrewd and cunning as Lucius' character, who made sure to get rid of Dark magic items earlier wouldn't have intended to use it on Harry. Isaacs, however, improvised and chose to ad-lib the beginning "Avada..." of the Killing Curse before Dobby attacked him.
In Deathly Hallows, Hermione faced a real test of her physical and psychological stamina. After being on the run from a bunch of Snatchers, the gang were taken to Malfoy Manor, where Bellatrix proceeded to torture Hermione using the Cruciatus Curse.
When Harry critically injured Draco Malfoy with the Sectumsempra curse, it was actually enough to have him expelled, as Professor Minerva McGonagall stated Harry was lucky not to have been, due to Snape giving lenience to prevent others from finding out that he was the one who invented the curse (Despite the fact Draco ...
Harry truly realizes this when he casts the Cruciatus Curse on Amycus Carrow after Carrow spits in the face of Professor McGonagall in the Ravenclaw dormitory, stating his understanding of the anger one must feel to make such a curse be effective.
Originally Answered: Why didn't Tom Riddle simply use "Avada Kedavra" to kill Harry in The Chamber of Secrets? Tom riddle did not use the killing curse in the chamber of secrets on Harry because as explained by fake Moody in the Goblet of fire, the killing curse requires a phenomenal amount of magical energy.
Malfoy spots Harry and casts a Cruciatus curse; Harry, defending himself, using the Half-Blood Prince's Sectumsempra spell without knowing its effects. To his horror, it gashes Draco's face and chest, spilling his blood everywhere. Moaning Myrtle flies off, screaming.
Harry Potter: Why Voldemort Didn't Use Avada Kedavra On Snape - IMDb. Voldemort killed Snape in Harry Potter And The Deathly Hallows Part 2 using his Horcrux snake Nagini instead of his favorite Unforgivable Curse, Avada Kedavra.