You can learn all of the three Unforgivable Curses and use it against others without penalty in Hogwarts Legacy. Although it is extremely dangerous to use these spells in the wizarding world, it is certainly an asset for a witch or wizard. It's the most powerful spell in the Dark Arts and is used as a last resort when everything fails.
In Hogwarts Legacy, how do I unlock Avada Kedavra's spell?
To unlock Avada Kedavra, you need to complete several quests for Sebastian Sallow. His quest line will help you unlock the three Unforgivable Curses. This will be the third and last quest in Sebastian's quest line which will take you inside a cave populated with inferni. You and Sebastian will defeat Solomon Sallow inside the cave.
Sebastian will send you an Owl Post to complete the quest, so be sure to not miss it. After you have completed the quest, go to Sebastian, who will teach you the spell. You can use it without worrying about going to Azkaban in Hogwarts Legacy.
Avada Kedavra, also known as the Killing Curse, is a dangerous spell that can kill someone in an instant without any injury. Only Harry Potter has been known to survive it. However, in Hogwarts Legacy, you can terminate fights in an instant if you are ready to use this spell. For example, the troll fights and boss fights, which occur later in the game, can conclude in a matter of seconds if you use Avada Kedavra.
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