She began working at Zynga in late 2010, where she continued to work with games such as Hidden Chronicles. She left the company in 2017.
In June 2012, it was announced that Marx would be writing the character of Amethyst, Princess of Gemworld in a revival of the comic book series Sword of Sorcery, which was released in August 2013.
She has also authored a writing manual, Writing for Animation, Comics, and Games. The book covers how to write for multiple mediums and formats.
In 2000, Marx won the Animation Writers Caucus Animation Award from the Writers Guild of America for her contributions to the field of animation writing.
Best Computer Adventure game 1990, by Video Games and Computer Entertainment Magazine, for Conquests of Camelot: The Search for the Holy Grail
Best Adventure game 1991, by Computer Game Review and Enchanted Realms, for Conquests of the Longbow: The Legend of RobinHood
↑Rogers, Vaneta (June 8, 2012). "DC Adds Four to New 52, Including DiDio's Phantom Stranger". Newsarama. Archived from the original on September 30, 2013. Retrieved June 10, 2012. This new series... will launch with the return of Amethyst to the New 52. Written by Christy Marx with art by Aaron Lopresti, the comic will show how Amethyst finds out she's the lost princess of Gemworld.