Waver Velvet (Japanese: ウェイバー・ベルベット, Hepburn: Weibā Berubetto) is a fictional character who first introduced in Type Moon's light novel prequel to Fate/stay night, Fate/Zero by Gen Urobuchi.

The character was created by Urobuchi in an attempt to balance the cast of Fate/Zero with Waver displaying more weak traits as young man who would develop into a fine adult through the events of the narrative.

His El-Melloi persona was written by Makoto Sanda as a grown man sharing detective dynamics with his assistant Gray inspired by Sherlock Holmes.

In regards to his role in his spin-off series, Waver stood out from how he comes across as a more appealing main character than in Fate/Zero due to his growth as a teacher as he deals with multiple students.

After discovering what happened to his former teacher and feeling responsible for his death, Waver borrowed a loan from an old friend named Melvin Weins to purchase the El-Melloi Classroom and began to teach Modern Magecraft.

In battle, he uses bagua mirrors that shoots energy beams and can cast various elemental spells such as earth, wind and fire.

From the original light novel, Urobuchi wrote Waver as a young child who would seek his path to become an adult going through a traumatic events.

[12][13] Takeuchi was satisfied with the way Waver was received in the light novels and hoped the anime adaptation would demonstrate a similar success.

[14] The prospect of seeing another author write about Waver as he was developing as a mage, able to do nothing but sit back and watch as events unfolded around him, was a difficult part for Urobuchi.

Urobuchi describes him as "the gentleman who had polished his powers of analysis, bearing a cunning like an old man's wisdom, while still hiding the distortion of his youth somewhere in his heart" making him, in the end, an "enchanting character.

The relationship between these two characters was primarily centered by the Gray's weaker persona who constantly thinks about his master and the writer aimed to attract the female demographic throughout this.

[18] While in English, he was voiced by Lucien Dodge in Fate/Zero, Unlimited Blade Works, Fate/Apocrypha and Case Files, and by Leraldo Anzaldua in the first two seasons of Fate/kaleid liner Prisma Illya.

[2] Yuya Matsushita and Shinichiroh Ueda portrayed his older and younger self, respectively, in the stage play adapting the Adra Castle Separation chapter from the light novel.

[30] In regards to Waver's role in the spin-off The Case Files of Lord El-Melloi II, Manga.Tokyo found his personality appealing describing him as "bolder" as well as underdog.

[31] Krestel Swift from The Fandom Post described the older Waver as "uncharacteristically suave hunk with seemingly neither awkwardness nor a sense of humor" and praised the series how the narrative of Lord El-Melloi II handles his growth ever since Fate/Zero due to his different personality.

[32] Anime News Network described him as a funny character based on his reactions despite the series' dark tone as the episodes often involve murder.