Smosh

Smosh is a YouTube comedy duo consisting of best friends Anthony Padilla and Ian Hecox. They are currently the fourth-most subscribed channel on YouTube with over 4 billion views and 21 million subscribers. Nice Peter has hinted at their appearance many times before, and they finally debuted in Artists vs TMNT.

Information
Smosh was originally founded by Anthony Padilla in 2002, later joined by Ian Hecox, but it wasn't until 2005 that their YouTube account was created. Early videos on their YouTube channel included lip-syncing famous theme songs, such as Power Rangers, Mortal Kombat, and Pokémon, the latter of which became the most viewed video on YouTube at the time until it was removed for copyright. Smosh is also known for its cast of recurring characters, such as Ian's mother Cheryl, That Damn Neighbor, Brad Padilla, and Charlie the Drunk Guinea Pig. They currently have several channels, which include Smosh Games, Smosh 2nd Channel, Shut Up! Cartoons, and ElSmosh. They also have a video game available for free on the App Store, which was based on their popular Food Battle series. Furthermore, a feature film starring Anthony, Ian, Jenna Marbles, Grace Helbig, Shane Dawson, and other YouTubers titled Smosh: The Movie, distributed by Lionsgate, was released in theaters on July 24th, 2015. You can purchase the movie here.

Anthony Padilla:

 * Raphael da Sanzio Urbino

Ian Hecox:

 * Michelangelo Buonarroti

Trivia

 * Smosh, along with PewDiePie and Jenna Marbles, are the only YouTubers to appear in an ERB that have more subscribers than ERB itself.
 * PewDiePie was the only one who appeared as a cameo.
 * Both PewDiePie and Smosh appeared in season finales.
 * Smosh is the only duo to appear in an ERB that has more subscribers than ERB themselves.
 * They are the third guest duo to appear in a battle, after Rhett & Link and Key & Peele.
 * In an episode of Rhett & Link's podcast, Ear Biscuits, Rhett and Link revealed that they had performed an episode of Epic Rap Battles of History with Smosh.
 * This episode turned out to be Artists vs TMNT.
 * Anthony hinted towards Raphael by showing that they were reading a book on him in one of his and his girlfriend's videos on their separate channel, WatchUsLiveAndStuff, now named Kalel Kitten.
 * Nice Peter once mentioned that he'd like to have Anthony play Ash Ketchum, but only if Ian played Pikachu.
 * Peter wanted them to portray Bill & Ted against Lewis & Clark; however, Smosh disliked the idea as they knew little about the characters.