The group, who worked at Softdisk in Shreveport, Louisiana developing games for the "Gamer's Edge" video game subscription service and disk magazine, was composed of programmers John Romero and John Carmack, designer Tom Hall, artist Adrian Carmack, and manager Jay Wilbur. After the release of the game in December, and the arrival of the first US$10,500 royalty check from shareware publisher Apogee Software, the team quit Softdisk and started their own company, id Software. As part of the settlement with Softdisk—made because the team had created the game on their work computers, both in the office after hours and by taking the computers to John Carmack's house on the weekends—they agreed to make a series of games for Softdisk's Gamer's Edge subscription service. As the team began to explore creating another set of "Commander Keen" games, they made a prototype game for Softdisk, "Commander Keen in Keen Dreams", to fulfill their obligations while also helping improve the next full set of "Keen" games. For "Invasion of the Vorticons", John Carmack and Romero focused exclusively on the programming, while Adrian Carmack joined late in development and had a personal art style that did not match with the game. As a result, the game was largely shaped by designer Tom Hall's personal experiences and interests. Keen's red sneakers and Green Bay Packers football helmet were items Hall wore as a child, dead enemies left behind corpses due to his belief that child players should be taught that death had permanent consequences, and enemies were based loosely on his reading of Sigmund Freud's psychological theories, such as that of the id. The team reprised their roles for both "Keen Dreams" and "Goodbye, Galaxy", with the addition of programmer Jason Blochowiak for "Goodbye, Galaxy", and changed the game engine and design for the next "Keen" games: an increase in graphical quality with parallax scrolling to make the background move at a different speed than the foreground, a pseudo-3D view rather than a side-on view, ramps rather than solely flat surfaces, support for sound cards, and changes to the design based on player feedback. The level maps were designed using a custom-made program called Tile Editor (TEd), which was first created for "Dangerous Dave" and was used for the entire "Keen" series as well as several other games. The working title for the game was "Commander Keen II - Goodbye Galaxy".