Waver Velvet

The third generation magus of the Velvet household. Though to put that in perspective, the first generation was his grandmother, who was the lover of a certain magus and picked up the very basics of sorcery from their pillow talk. The second generation, Waver's mother, only dabbled as a way to honor her mother's memory. Waver was the first member of his family to seriously follow the path of sorcery, which is why his circuit count and crest quality are both the lowest of the low.
Though his mother found the Association's hierarchical system annoying and disapproved of her son seeking out tutelage from a proper mentor, Waver himself was strongly drawn to sorcery. After both his parents died of illness, he gave away all of his family's possessions, scraped together just enough money to cover tuition, and entered the Clock Tower without a penny to his name. As a result, he endured countless hardships and failures, and eventually resorted to gambling everything on the Holy Grail War.
Though he doesn't possess even the most basic prerequisites to actually practice sorcery, his power of observation and insight give him remarkable talent as a researcher. In fact, had he insisted that “Sorcery is a subculture!” and started a business as a critic, he could have taken the world by storm. But of course, he would have been obliterated by the Association, so his inborn talents took another form.
To use running as metaphor, though his leg strength is just the absolute worst, he is capable of imagining the perfect running form. While he can never be an athlete, his talent shines as a coach.
He was initially conceived of as a Nobita-like “King of Cowards,” a breath of fresh air in the grim world of Zero. By the time the book was finished, though, his character had grown to the point you might actually mistake him as the protagonist.

Fate/Zero material: Fate/Zero Encylopedia
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→See the entry on Lord El Melloi II.

Fate/Apocrypha material: Fate/Apocrypha Encylopedia