Cogliostro (/kɒɡliˈoʊstroʊ/; also Cog) is a fictional character in Todd McFarlane's Spawn comic series, set in the Image Universe. Cogliostro was created in 1993 by author Neil Gaiman and artist Todd McFarlane and introduced in Spawn issue #9. Originally depicted as a supporting character, he becomes an antagonist as the series progresses, eventually becoming the supervillain Sinn.