McMillen has been a lifelong resident of Santa Cruz, California. He went to school at Soquel High School. He is especially fond of drawing, his favorite subjects being monsters.
Many of these drawings can be seen by unlocking The Box in one of his games, The Basement Collection.
McMillen"s initial graphic work was in independent comics. While he has largely abandoned this field in favor of video games, he has released a series of comics featuring Meat Boy, the title character in the video game Super Meat Boy, as a promotional tie-in for the game.
His most well-known games are the Flash-based game Meat Boy, and its much-lauded sequel Super Meat Boy, which has been released for the Xbox 360 platform and Personal Computer. McMillen is also known for the award-winning games Gish, Aether, The Binding of Isaac and Coil. His game Coil was nominated for the Innovation Award at the 2009 Independent Games Festival.
McMillen was the original character artist and animator on Braid, before those assets were replaced by the work of David Hellman.
His game Aether was a 2009 IndieCade finalist and received an honorable mention. Super Meat Boy
McMillen and programmer Tommy Refenes established Team Meat, an independent game production company, with the intent that they would never utilize a third-party publisher. Their first game, Super Meat Boy, was released on October 20, 2010 on the Xbox 360 via Xbox Live Arcade, and on Valve Corporation"s digital distribution system Steam on November 30, 2010.
A release was planned for the Nintendo Wii, but was canceled.
According to Kotaku, problems arose due to the file size limitations of the Wii"s WiiWare Channel. A retail version of the game was released on April 5, 2011.
Due to Sony"s initial disinterest in the game, Team Meat entered into contractual obligations that prohibit the game from being released for the Sony PS3. McMillen and Refenes responded to the success of Super Meat Boy and the impossibility of a sequel in a brief statement that read, "We feel like we did lieutenant.the 1st time." In the April 2011 issue of Game Developer, McMillen said that during the development of Super Meat Boy he had to go under emergency gallbladder surgery which put him $50,000 in debt because he could not afford health insurance.
McMillen and Refenes" development of Super Meat Boy was featured in the film Indie Game: The Movie.