The Final Boss of the Internet is a mythological character that is supposedly found at the "final level" of the Internet if it were imagined as a video game. The term is generally used to refer to any object, person or place that can be seen as very powerful or difficult to overcome.
According to an article on the archive site The Armory, the first video game to incorporate defeatable bosses was the 1975 role-playing game dnd. The game incorporated many of the elements behind the table top game Dungeons & Dragons, and was designed for the PLATO computer system. The point of the game was to defeat a final boss named "Gold Dragon" who protected an orb which would end the game once collected by the player.
The earliest known reference to the Internet as a video game with an end boss comes from an Internet Relay Chat (IRC) log archived on Bash.org as early as September 2002 according to Google cached data. This shares the same source of origin for the expression "you win the Internet".
<BombScare>… i beat the internet
<BombScare>… the end guy is hard
The phrase "final boss of the Internet" is typically used in jest as a way of saying someone or something is so strong, mysterious, or weird looking, that they must be the Internet's last standing ruler. The first Urban Dictionary definition for "final boss of the Internet" was submitted by user Krem on January 9th, 2005.
Sometimes, people jokingly refer to the internet as a game of sorts, and, like all games, it must have a final boss. Who or what the final boss truly is has been disputed, but one of the more accepted claims is that the position is held by Scott Willoughby, aka StaringVacantly.
The earliest known archived 4chan thread mentioning the final boss was titled "Ulilillillia – the final boss of the internet", about game designer and author Nick Smith (aka ulillillia), was posted on November 20th, 2007.
On October 8th, 2008, the tech blog Romhack published a post titled "Anonymous: final boss of the Internet?" which described the culture of Anonymous on 4chan. On July 8th, 2009, a video titled "Rainbow Bunchie (aka Final Boss of the Internet)" featuring a rainbow colored animated Bunchie was uploaded to YouTube by user martianmedia. The video accumulated over 1.7 million views within 2.5 years.
On September 5th, 2009, the first Yahoo Answers question for "Who is the final boss of the internet?" was submitted by user Vault Boy. The top ranked answer chosen by voters was "Anon" by user nezvoratue.
On October 1st, 2011, a post titled "Final Boss of the Internet" was posted to the humor site Cracked claiming that Anonymous was not the final boss of the Internet. A Facebook page for "The Final Boss of teh Internets" has received 308 likes as of February 14th, 2012.