"I Herd U Liek Mudkips" is a catchphrase that became popular through its frequent usage on 4chan in the mid-2000s. Variations on the spelling and the addition of “so” to the beginning of the phrase can also be found. Although its meanings are obscure, the phrase is commonly used as an identifier amongst 4chan users outside of the imageboard community, similar to the usage of "The Narwhal Bacons at Midnight" on Reddit.
Mudkip is a blue and orange water-type Pokemon character who first appeared in the Ruby and Sapphire games, released in the US in March 2003. The phrase "so i herd you like mudkips" originated in early 2005 with the deviantArt group MudKipClub. The account was founded on October 5th, 2004 as a place for users to share Pokemon fanart. The club was not limited to Mudkips, however, as the first artwork depicted the character's final evolution, Swampert. The owner of the community began posting the phrase "so i herd you like mudkips" on other users' comment walls as early as February 7th, 2005. While the motive behind the comments are unclear, the wall messages served as an invitation to join the MudKipClub community.
Throughout 2005 and 2006, a copypasta story about a boy dressed as Ash Ketchum humping a plush mudkip toy began circulating 4chan. The copypasta story was reposted in 2007 on 4chan, deviantArt Forums Playstation Universe Forums and My Confined Space. In 2008, it was spotted on the Naruto Forums, eBaum’s World Forum, and NeoGAF Forums. The story was eventually added to the Copypasta Archive in February 2010.
By the end of 2005, a variation of the phrase was used as a nonsequitur comment on Fark.Several YTMNDs with the phrase were also created throughout 2006, with the first appearing on January 21st, 2006. “Mudkip” was first added to Urban Dictionary on January 11th, 2007. Variations on the word included “Mudkip”and “Mudkipz” were also added that year. As the phrase continued to spread across different sites, other creative misspellings of the phrase emerged with “like” misspelled as "liek" and “mudkips” spelled with a z. In 2008, during the Project Chanology protests, many Anonymous protestors used mudkips on their signage or asked other people if they liked mudkips as a way of identifying each other.
Mudkips have many Facebook fan pages, but the two largest have over 34,000 likes combined. It is also listed in Shii's Internet Quotations dictionary and there are over 10,000 results for "mudkips" on deviantArt.
Search for variations upon the phrase peaked in April 2008, do to a deviantArt April Fool's Day prank where all user avatars were changed into Mudkips. "Mudkipz" with a Z overtook the traditional pluralized spelling in February 2009.