MatPat

Patrick first created a YouTube account under the name "MatthewPatrick13" in 2009. He uploaded numerous videos of his performances and auditions for musical theatre, including one where he sang "It Takes Two" from the musical Hairspray.

On April 18, 2011, he uploaded the first episode of Game Theory, discussing the relationship between reality and gaming in terms of science, math and culture. Inspired by the YouTube series Extra Credits episode Tangential Learning (March 23, 2011) he created Game Theory with the goal of creating "gaming's tangential learning experience" to show his abilities to companies that might watch his channel. He frequently uploads episodes covering Nintendo characters, as well as popular games such as Minecraft, Five Nights at Freddy's, Call of Duty and Pokémon, as well as numerous other games.[6][7] Early on in the show's history, MatPat was interviewed by Ronnie "Oni" Edwards, host of the Internet show Random Internet Encounters. After this meeting, Ronnie accepted MatPat's offer to be Game Theory's main editor, as well as hosting the show "Digressing & Sidequesting", which focused on game design. Before this, MatPat was the sole editor of the show. The first episode of Game Theory that Ronnie edited was How Much is Minecraft Diamond Armor Worth?[8] He occasionally uploaded videos commenting on the gaming market, as well as on other matters that he deemed noteworthy.[9] He gained subscribers and his videos were being posted on the front pages of sites such as ScrewAttack and GameTrailers.

During its life, The Game Theorists has hosted numerous spin-offs and separate shows. Some of the shows are only partly on The Game Theorists and consist of more episodes on the creators' channels. The Game Theorists reached one million subscribers on December 17, 2013, and 11 million in 2018.

On May 12, 2014, Patrick created a second channel called The Film Theorists where he debuted his second show, Film Theory. The first video was uploaded on June 2, 2015, focusing on the prophecy of the chosen ones in the Harry Potter film series.[10] Film Theory follows the same formula as Game Theory, but focuses on films and series as well as the film industry instead of gaming. Within a month of the first episode, The Film Theorists reached one million subscribers.[11]

Patrick on the Vlogbrothers in April 2016

On June 8, 2016, Patrick posted via his YouTube channel his new show, MatPat's Game Lab, on Google's paid subscription service, YouTube Red. The show mainly focuses on placing video game players in real life scenarios mimicking scenarios that occur in video games, such as bomb defusing, parkour, and military training.[12][13][14]

Patrick started a Let's Play series called GTLive on August 26, 2015, [15] where he streams mostly gameplay with his wife Stephanie on the GTLive channel he created on September 14, 2015. Streams are usually conducted at 4 pm PST. Regular guest appearances on the streams include Jason, the producer of GTLive, the co-producer Chris, who became part of the streams after standing in for Jason during his wedding, the Patricks' cat Skip, also known as “CatPat,” Peepachu, a cushion in the form of a yellow, rabbit-shaped Peep and a llama plushie, referred to as "Drama Llama". Repeated themes of this live stream include "Mario Maker Wednesday" (abbr. “MMW”), "Motion-Control Thursday" and "Scary Games Friday" (abbr. “TGISGF” for “Thank Goodness It's Scary Games Friday”), also occasionally known as "Spoopy Games Friday". A common feature is the 'clap-and-a-half' which Patrick reclaimed from his seventh grade Social Studies teacher. On one live stream, they used Verizon's in-game Minecraft smartphone for ordering pizza as well as taking "the worlds largest [in-game] selfie".[16]

Starting on October 3, 2016, the Monday streams became part of YouTube Gaming Primetime and are therefore scheduled for 3 pm to 5 pm PST. It also includes a voting mechanism, which can be used by Patrick to conduct quick polls.[17]

As of 2016, GTLive streams three days per week on average, garnering roughly 80,000 to 110,000 total viewers for each stream.

On April 3, 2017, Patrick announced that the show would go on a brief hiatus until April 25, 2017, due to VidCon Europe and scouting different filming locations.[18] Due to VidCon Australia, the show was again paused on September 4, 2017[19] and returned on September 26, 2017.[20]

Patrick was involved in the web series TOME: Terrain of Magical Expertise. He gained the series more attention and exposure by uploading a re-mastered version of the first episode on the channel on October 1, 2013, and then providing a platform for the series.[21][22] Patrick, as well as many of the Game Theorists members, also provided their likeness as opponents in the RPG video game adaption in the works. Patrick's character, Mattheorist, displays Green Lantern-like qualities with the ability to manifest green energy projectiles and creatures. Their fate in the final project remains undetermined as it's subject to change due to legal issues.[23]