About
Ryuunosuke Uryuu is a major antagonist from the light novel and anime series Fate/Zero. He is a serial killer and the Master of Caster during the Fourth Holy Grail War. Unlike the other Masters, however, he has no interest whatsoever in obtaining the Grail and merely wishes to use Caster as a tool for his killing spree. He serves as the main antagonist of the first season of the anime (as well as the corresponding novels).
