|This article is about a/an villain and a Horror in Garo: Honoo no Kokuin|
Guillermo was originally a man who was executed for attempting to kill the king, now his patched body is host to a Horror named Metaclim.
Honoo no Kokuin
After Mendoza receives reports that a father and a son were practicing strange techniques, he dispatches a squad of soldiers with a Horror-possessed Guillermo as their captain. Once at the place, Metaclim sends the signal to burn the house Leon was on, and enters the burning house to confront Leon. Leon transforms and brings the fight outside, where Metaclim reveals his true form, but is eventually slain.