Editing Commander Keen (section)

===''Invasion of the Vorticons''===
{{see also|Commander Keen in Invasion of the Vorticons#Development}}
In September 1990, John Carmack, a game programmer for the ''Gamer's Edge'' video game subscription service and [[disk magazine]] at Softdisk in [[Shreveport, Louisiana]], developed a way to create graphics which could smoothly scroll in any direction in a [[PC game|computer game]]. At the time, [[IBM PC compatible|IBM-compatible general-purpose computers]] were not able to replicate the common feat of [[video game console]]s such as the [[Nintendo Entertainment System]], which were capable of redrawing the entire screen fast enough for a side-scrolling video game due to their specialized hardware. Carmack created [[adaptive tile refresh]]: a way to slide the majority of the visible screen to the side both horizontally and vertically when the player moved as if it had not changed, and only redraw the newly-visible portions of the screen. Other games had previously redrawn the whole screen in chunks, or like Carmack's earlier games were limited to scrolling in one direction.<ref name="IGNid"/><ref name="MOD4851"/> He discussed the idea with coworker Tom Hall, who encouraged him to demonstrate it by recreating the first level of the recent ''[[Super Mario Bros. 3]]'' on a computer. The pair did so in a single overnight session, with Hall recreating the graphics of the game—replacing the player character of [[Mario]] with Dangerous Dave, a character from [[Dangerous Dave|an eponymous previous Gamer's Edge game]]—while Carmack optimized the code. The next morning on September 20, the resulting game, ''Dangerous Dave in Copyright Infringement'', was shown to their other coworker John Romero. Romero recognized Carmack's idea as a major accomplishment: [[Nintendo]] was one of the most successful companies in Japan, largely due to the success of their [[Mario (franchise)|''Mario'' franchise]], and the ability to replicate the gameplay of the series on a computer could have large implications.<ref name="MOD4851"/>

Romero felt that the potential of Carmack's idea should not be "wasted" on Softdisk; while the other members of the Gamer's Edge team more or less agreed, he especially felt that their talents in general were wasted on the company, which needed the money their games brought in but in his opinion neither understood nor appreciated video game design as distinct from general software programming. The manager of the team and fellow programmer, Jay Wilbur, recommended that they take the demo to Nintendo itself, to position themselves as capable of building a PC version of ''Super Mario Bros.'' for the company. The group—composed of Carmack, Romero, Hall, and Wilbur, along with Lane Roathe, the editor for Gamer's Edge, decided to build a full demo game for their idea to send to Nintendo. As they lacked the computers to build the project at home, and could not work on it at Softdisk, they "borrowed" their work computers over the weekend, taking them in their cars to a house shared by Carmack, Wilbur, and Roathe, and made a copy of the first level of the game over the next 72 hours.<ref name="MOD5257"/><ref name="ARSdemo"/> They credited the game to Ideas from the Deep, a name Romero had previously used for some Softdisk projects.<ref name="ARSdemo"/><ref name="IdTwilight"/> The response from Nintendo a few weeks later was not as hoped for, however; while Nintendo was impressed with their efforts, they wanted the ''Mario'' series to remain exclusive to Nintendo consoles.<ref name="MOD5257"/>

Around the same time as the group was rejected by Nintendo, Romero was approached by [[Scott Miller (entrepreneur)|Scott Miller]] of [[3D Realms|Apogee Software]], who wanted him to publish more levels for his previous ''Pyramids of Egypt—''an adventure game where the player navigates mazes while avoiding Egyptian-themed traps and monsters—through Apogee's [[shareware]] model.<ref name="MOD5862"/> Miller was pioneering a model of game publishing where part of a game would be released for free, with the remainder of the game available for purchase from Apogee.<ref name="IGNid"/> Romero said he could not, as ''Pyramids of Egypt'' was owned by Softdisk, but that it did not matter as the game he was now working on was much better, and sent Miller the ''Mario'' demo. Miller was impressed, and the team agreed to create a new game for Apogee before Christmas of 1990—only a few months away—split into three parts to match Apogee's shareware model of giving away the first part for free to attract interest in the whole.<ref name="MOD6366"/><ref name="MOD5862"/> Hall suggested a console-style platformer in the vein of ''Super Mario Bros.'', as they had the technology made for it; he further recommended a science fiction theme, and developed a short introduction that convinced the team to make ''Commander Keen in Invasion of the Vorticons''.<ref name="MOD6263"/>

{{Blockquote
|text=Billy Blaze, eight-year-old genius, working diligently in his backyard clubhouse has created an interstellar starship from old soup cans, rubber cement and plastic tubing. While his folks are out on the town and the babysitter has fallen asleep, Billy travels into his backyard workshop, dons his brother's football helmet, and transforms into...

COMMANDER KEEN—defender of Earth!

In his ship, the Bean-with-Bacon Megarocket, Keen dispenses galactic justice with an iron hand!
|source=The original concept for ''Commander Keen'', used in the introduction of "Marooned on Mars".<ref name="3DRretro"/>}}

The Ideas from the Deep team could not afford to leave their jobs to work on the game full-time, so they continued to work at Softdisk, spending their time on the Gamer's Edge games during the day and on ''Commander Keen'' at night and weekends using Softdisk computers. The group split into different roles: Hall became the game designer and creative director, John Carmack and Romero were the programmers, and Wilbur the manager.<ref name="MOD6366"/> They invited artist [[Adrian Carmack]] from Softdisk to join them late in development, while Roathe was soon removed from the group. Ideas from the Deep spent nearly every waking moment when they were not working at Softdisk from October through December 1990 working on ''Commander Keen'', with Wilbur forcing them to eat and take breaks.<ref name="MOD6366"/><ref name="3DRretro"/>

The game's design was largely driven by Tom Hall: Romero and especially John Carmack were focused almost exclusively on the programming; Wilbur was not involved in the game's design; and Adrian Carmack joined late in development and found the project's "cute" art style, till then mostly created by Hall, far-removed from his preferred, darker, style.<ref name="MOD6366"/><ref name="ECMint"/> Hall's personal experiences and philosophies, therefore, strongly impacted the game: Keen's red shoes 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, ego and super-ego#Id|id]].<ref name="MOD6366"/> Other influences on Hall for the game were ''[[Duck Dodgers in the 24½th Century]]'' and other [[Chuck Jones]] cartoons, and "The Available Data on the Worp Reaction", a short story about a child constructing a spaceship.<ref name="3DRretro"/><ref name="ECMint"/> Keen's "Bean-with-Bacon" spaceship was taken from a [[George Carlin]] skit about using bay leaves as deodorant so as to smell like soup. Keen was intended to be a reflection of Hall as he had wanted to be as a child.<ref name="3DRretro"/> The team separated the game from its ''Super Mario Bros.'' roots by adding non-linear exploration and additional mechanics like the pogo stick.<ref name="IGNid"/> A suggestion from Miller that part of the popularity of ''Super Mario Bros'' was the presence of [[easter egg (media)|secrets and hidden areas]] in the game led Hall to add several secrets, such as an entire hidden level in the first episode, and the "Galactic Alphabet".<ref name="MOD6676"/> 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.<ref name="TE5GameUltra"/>

As the game neared completion, Miller began to market the game to players. Strongly encouraged by the updates the team was sending him, he began heavily advertising the game in all of the [[bulletin board system]]s (BBS) and game magazines he had access to. The game was completed in early December 1990, and on the afternoon of December 14 Miller began uploading the completed first episode to BBSs, with the other two episodes listed as available for purchase as a mailed plastic bag with floppy disks for US$30 (~${{Format price|{{Inflation|index=US|value=30|start_year=1990}}|0}} in {{Inflation/year|US}}).<ref name="MOD6366"/><ref name="MOD6676"/> After the arrival of the first royalty check from Apogee, the team planned to quit Softdisk and start their own company. When their boss and owner of Softdisk Al Vekovius confronted them on their plans, as well as their use of company resources to develop the game, the team made no secret of their intentions. Vekovius initially proposed a joint venture between the team and Softdisk, which fell apart when the other employees of the firm threatened to quit in response, and after a few weeks of negotiation the team agreed to produce a series of games for Gamer's Edge, one every two months.<ref name="MOD6676"/>