As fans may remember, when the Black Clover movie revealed its first teaser, several fans raised doubts over its status in the storyline. As the story never appeared in the manga, fans were left confused over how to treat the movie.
However, as the storyline fit in perfectly with the timeline between the Elf Reincarnation Arc and Heart Kingdom Joint Struggle Arc, fans eventually started considering the movie an anime original or a canon storyline.
Fortunately, the manga's latest spoilers connected with the movie's storyline, confirming the movie developments as canon.
Disclaimer: This article contains spoilers from the Black Clover manga.
Black Clover movie's Millie Maxwell returns in the latest spoilers

As fans may remember, Black Clover: Sword of the Wizard King introduced fans to several new characters. While the main focus was on the Wizard Kings, namely Conrad Leto, Edward Avalaché, Princia Funnybunny, and Jester Garandaros, the anime movie also introduced fans to Millie Maxwell.
Millie Maxwell, similar to the other Wizard King characters, never appeared in the manga and was an original character created for the movie. She was the coordinator of the Magic Tool Research Lab Branch 0 and conducted research together with Sally. However, the alleged spoilers for the manga's latest chapters finally made her a manga canon character.

As seen in Black Clover chapter 382 spoilers, just as the Diamond Kingdom mages attacked Paladin Moris Libardirt, Millie Maxwell suddenly spoke to everyone from the Research Lab. While she wished to contribute to the battle earlier, she hated going in without a proper plan. Hence, despite working with Sally, Rades Spirito, Valtos, and Makusa North, it took her some time.
With the Clover Kingdom being in trouble, she had formulated a plan that could turn the tide on the battlefield. As derived from Sally's study of Asta's magicless body, the Research Lab team developed a special form of ammunition that worked on Lucius Zogratis's legless angels.

When hit by the ammunition, one cannot use magic for five seconds. Millie Maxwell wanted to capitalize on those five seconds by having Rades Spirito use his Soul Corpse Magic to trap the legless angels' souls and send them to the heavens.
While the alleged spoilers did not focus a lot on Millie Maxwell, they not only made her a canon character but also confirmed that the events that took place in the Black Clover movie had actually taken place in the same manga timeline.

With that, the spoilers from Black Clover chapter 382 effectively confirmed that the Black Clover movie was canon. Hopefully, the events from Black Clover chapter 382 spoilers do not end up as the only Black Clover movie reference, and we get more references and connections in future chapters.
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