Gregory Todd Farshtey is an American writer, best known for his work on the Bionicle series of novels (2004–2010) and the Bionicle comics (2001–2010).

Greg Farshtey began writing seriously in high school, where he wrote and edited a weekly satirical newsletter, Lunatic News and World Report. After college, he worked as a reporter and sports editor for securing an editorial position with West End Games. Over the next seven years, he authored or co-authored over 35 roleplaying game books and helped to create the Shatterzone and Bloodshadows roleplaying game universes. He also authored a handful of short stories and three novels, "The River of God," "Hell's Feast," and "Demon's Dream."

Farshtey joined The LEGO Group in late 2000, writing for the LEGO Mania Magazine and the BIONICLE comic series. He now writes and edits six editions of the bi-monthly LEGO Club Magazine, as well as the LEGO BrickMaster Magazine and LEGO Club Jr. Magazine.

Farshtey is the author of over 30 BIONICLE novels, seven EXO-FORCE books Knights Kingdom, and every issue of the BIONICLE comic (2001–2010) and a small number of BIONICLE guidebooks. His work has been published in English, Russian, Chinese, French, Polish, and German, among other languages. He also wrote the story for the BIONICLE DVD movie, BIONICLE: The Legend Reborn (2009). He has made numerous public appearances at San Diego Comic-Con, bookstores, and libraries.