Two Legged Horse (a.k.a Retarded Running Horse) is an animated GIF of a running horse with its head photoshopped on to its hind legs. The animation was paired with the gibberish chorus from Chacarron Macarron and uploaded on YouTube, where it spawned many other videos with similarly photoshopped animals.
On March 10th, 2006, the GIF was made into a video by YouTuber bergerking24 where it was set to the Star Wars main title "The Ice Planet Hoth." As of March 2012, the video has over 11.8 million views.
In mid-2006, British animator Cyriak created two similar GIFs featuring a llama and an elephant walking on two legs. He initially uploaded them to his personal website and later used the elephant in a YouTube video titled “cyriak’s animation mix”, uploaded on October 8th, 2006.
On December 14th, 2007, YouTuber caitlinrox1234 re-uploaded the video as "Retarded Running Horse," changing the background music to Chacarron Macarron by El Chombo. As of March 2012, this version has over 48.5 million views and has been shared on Facebook over 1 million times. Numerous other songs have been since paired with the "Retarded Running Horse," including the Benny Hill chase theme, the Deathnote theme song and Nyanyanyanyanyanyanya.
Retarded Running X
In September 2010, Cyriak’s elephant was used as a derivative of “Retarded Running Horse,” sparking other artists to create videos of two legged animals set to Chacarron Macarron. As of March 2012, there are over 3000 search results for "retarded running" animal videos.
Search for "two legged horse" began to pick up in September 2008, whereas search for "retarded running horse" began in April 2009 and overtook "two legged horse" in volume in February 2010. Search peaked in November 2011, when Chacarron Macarron was featured in the Gag Quartet's le Internet Medley.