Light Yagami is the anti-hero, turned into the primary antagonist, in the manga, and the resulted anime series, Death Note. One of the influential and acclaimed anime characters of modern fiction, Light Yagami is an expert high-school student and a genius tactician, later turning into a psychotic and prejudiced killer with the use of the mysterious weapon, known as "Death Note", given by the Japanese god of death Ryuk. His role and portrayal are infamous in the series, as he focused on creating a pure and perfect world, where he would cleanse its criminals and evildoers, appointing himself as the new "God" of his world. Throughout the course of the original series, Light Yagami clashed with super-detective "L", eventually defeating him, but not before accepting defeat from "L"'s acquaintances and Ryuk's ultimate judgement.
Regarding the villain wars context, Light Yagami is not featured physically. Yet, the archive footage of the character's death penalty is used in Heroes vs. Villains to represent the demise of several characters in the series, particularly Ichabod Crane and Clayton. Other than that, he doesn't make an official appearance in the series until Villains Battles he's a ally and spy of Mr. Swackhammer in order to keep a eye on Stromboli and Ratcliffe he's tried to kill Van Pelt but meet his doom with the hunter but later on he was bring back to life by his boss and tried to kill Scar but failed and get arrested by the Evil Lion and the Hyenas.