Here's the breakdown:
* The Battle of Hogwarts: Snape is a key player in the final battle against Voldemort. He plays a crucial role in protecting Harry, ultimately allowing him to confront Voldemort.
* Snape's Real Loyalty: He was secretly working for Dumbledore and against Voldemort, despite pretending to be on Voldemort's side.
* The Prophecy: Snape's actions were motivated by a prophecy, which stated that "the one with the power to vanquish the Dark Lord approaches...born to those who have thrice defied him, born as the seventh month dies..." Snape was instrumental in ensuring that the prophecy was fulfilled by protecting Harry from Voldemort.
* Nagini's Attack: In the final confrontation, Nagini, Voldemort's snake, attacks Snape, fatally wounding him.
* Snape's Death and Legacy: Snape dies with Harry watching, believing him to be a villain until Harry sees the memories Snape left for him. Snape's death is a pivotal moment, revealing his true loyalty and the depth of his love for Lily Potter, Harry's mother.
Snape's sacrifice is a powerful testament to the complexities of good and evil, love and loss, and the lengths to which one will go to protect those they care about.