Organ Trail is a "retro zombie survival game" that parodies the educational game series The Oregon Trail. It was initially released as a free Adobe Flash-based browser game, and later as a Facebook app. This version was developed by Ben Perez, Michael Block, and Ryan Wiemeyer. The game uses the Unity game engine. Director's Cut has sold 429,192 copies as of August 9, 2013. Most of the copies were sold on Humble Bundle, Steam and iOS. Most profits were made on the Steam and iOS platforms.