Black Clover's most wicked devil ultimately meets her end after years of tormenting the Silva family. Megicula's death brings closure to one of the manga's darkest storylines, where a mother's curse became the stimulus for family destruction. The Curse Devil's reign of torment spans generations.
In Chapter 303 of Black Clover, Nozel and Noelle Silva join forces to bring down Megicula. Noelle deals the killing blow that destroys the devil's heart, ending the curse that tormented their bloodline. This sibling partnership executes what neither could achieve alone.
Black Clover has built up the conflict between the Silva family and Megicula over numerous chapters. The Curse Devil was liable for putting a deadly curse on Acier Silva, the siblings' mother. This curse slowly depleted her until she eventually died, leaving her children to grow up without understanding the true cause of her death.

Nozel Silva took the burden of knowing the truth about his mother's fate. The curse prevented him from telling Megicula's involvement to anyone, including his siblings. This silence formed a rift between him and Noelle, as the family accused her of being responsible for their mother's death.
This climactic fight of the Black Clover series begins when Nozel realizes he cannot face Megicula alone. Years of trauma and remorse have shaped his character, but he finally understands that strength comes from working together. This acknowledgment marks a turning point in his relationship with Noelle and his approach to the battle.
The chapter begins as Nozel rescues Noelle from Megicula’s curse just in time. He then unleashes the full might of his Mercury Magic in a desperate, all-out assault on the devil. His assault severely damages Megicula but fails to deliver the killing blow.
Noelle’s Decisive Victory in Black Clover

The battle reaches its conclusion when Noelle joins her brother in the fight. Having grown tremendously in power throughout the series, she proves capable of matching her late mother's abilities. Her Saint Stage form allows her to fight on equal terms with the Curse Devil.
Noelle tells Megicula that it was defeated by the humans who refused to give up, and then she destroys Megicula's heart. The final attack represents more than just a victory in battle. It symbolizes the Silva family's triumph over the curse in Black Clover that has haunted them for years.
Chapter 303 of Black Clover delivers emotional resolution to the long-standing tragedy within the Silva family. The defeat of Megicula lifts the curse that prevented Nozel from speaking about his mother's true fate. This revelation allows the siblings to finally understand why their family dynamic became so fractured after Acier's death.

The chapter concludes with an emotional scene where Acier's soul appears to embrace her children one final time. This moment provides the healing that the Silva family has desperately sought.
As she fades, Megicula is stunned that mere humans were able to defeat her, admitting she misjudged their true strength. The devil's final thoughts reveal her growing interest in human emotions and bonds, which ultimately led to her downfall.
In the end, the question of who kills Megicula in Black Clover finds its answer in the combined efforts of the Silva siblings. While Nozel weakens the devil significantly, Noelle delivers the decisive blow that ends Megicula's reign of terror. This resolution provides emotional satisfaction for fans who have followed the Silva family's story throughout the series.