MARK SIEGEL has written and illustrated several award-winning and bestselling picture books and graphic novels. He is also the founder and editorial director of First Second Books. He lives with his family in New York. Find Mark at marksiegelbooks.com and the 5 Worlds team on Twitter at @5WorldsTeam. ALEXIS SIEGEL is a writer and translator who has translated a number of bestselling graphic novels, including Joann Sfar's The Rabbi's Cat and Penelope Bagieu's Exquisite Corpse into English and Gene Luen Yang's American Born Chinese into French. XANTHE BOUMA is an illustrator based in Los Angeles. Her work includes picture books, such as Little Sid, fashion illustration, and comics. Follow Xanthe on Tumblr at @yumbles and on Twitter at @xoxobouma. MATT ROCKEFELLER is an illustrator and comic artist from Tucson, Arizona. Currently living in Portland, Oregon. His work includes book covers, animation, and picture books such as Train, Rocket, and Pop! Follow him on Tumblr at @mrockefeller and on Twitter at @mcrockefeller. BOYA SUN is an illustrator and coauthor of the graphic novel Chasma Knights. Originally from China, Boya now lives in Los Angeles. Follow Boya on Tumblr at @boyasun and on Twitter at @boyaboyasun.