Simon Spurrier is a British comic writer who began his career in comics with 2000 AD and Warhammer Monthly. He broke into the US comic market with his original series, Gutsville, published by Image Comics with artist Frazer Irving. He's worked widely for American publishers including Marvel Comics, Dark Horse Comics, Image Comics, and Avatar Press. He is the writer of Extermination and Six-Gun Gorilla at BOOM! Studios. Jeff Stokely is an American illustrator and comic artist who has worked for Tokyopop and Udon along with doing character design for Mattel, Cryptozoic, and Square Enix. He illustrated the original graphic novels Reason for Dragons and Six-Gun Gorilla from BOOM! Studios.