Complex sentence: Spawn is a fictional character, an anti-hero that appears in a monthly comic book of the same name published by Image Comics as well as annual compilations, mini-series specials written by guest authors and artists and numerous cross-over story-lines in other comic books.
Split into simpler sentences: Spawn is a fictional character, an anti-hero that appears in a monthly comic book of the same name published by Image Comics. The character also appears in annual compilations, mini-series specials written by guest authors and artists, and numerous cross-over story-lines in other comic books.