Commander Keen in Invasion of the Vorticons

Did You Know?

• The game's three episodes are titled 'Marooned on Mars', 'The Earth Explodes', and 'Keen Must Die!'.
• After securing the final component in the first episode, Keen discovers a Vorticon mothership in orbit and returns home with a pet Yorp.

Development

In September 1990, John Carmack, a programmer at Softdisk, developed a method for smooth side-scrolling on IBM-compatible PCs using adaptive tile refresh, which slid the visible screen and redrew only newly visible portions. He discussed the idea with coworker Tom Hall, who encouraged a demonstration by recreating the first level of Super Mario Bros. 3. They did so overnight, with Hall recreating graphics and Carmack optimizing code, producing Dangerous Dave in Copyright Infringement.

John Romero recognized the achievement, as replicating Mario gameplay on PCs had large implications. The technique required a 16-color EGA graphics processor and did not meet Softdisk's coding guidelines. Carmack and his coworkers, including Romero, Hall, Jay Wilbur, and Lane Roathe, had previously developed a PC demo of Super Mario Bros. 3 but failed to convince Nintendo to invest. Scott Miller of Apogee Software then approached them to develop an original game for the Apogee shareware model.

Hall designed the three-part game, Carmack and Romero programmed it, Wilbur managed the team, and artist Adrian Carmack helped later. The team worked almost three months, often late into the night at Softdisk and at Carmack's home.

Reception

Commander Keen was an immediate success for Apogee, whose monthly sales had been around US$7,000. By Christmas 1990, sales reached nearly US$30,000; by June 1991, over US$60,000 per month. Scott Miller described the game as a little atom bomb. Its success led Miller to recruit his mother, hire his first employee, quit his other job, and move Apogee from his house to an office.

In 1995 the team estimated total sales of US$300,000 to $400,000. Chris Parker of PC Magazine called it a tremendous success. Apogee announced plans to license a Nintendo Entertainment System port, but none was created. Scott Miller estimated in 2009 that the trilogy sold between 50,000 and 60,000 copies.

Barry Simon of PC Magazine praised the Nintendo-like graphical capabilities, though he called the graphics well drawn but not spectacular in resolution. He noted the game was an arcade title not purchased for plot or originality, but found all three episodes fun to play and the scrolling graphics distinctive. PC World in 1992 termed it one of the most spectacular games available, praising superb sound and graphics. CQ Amateur Radio described it as Nintendo comes to the PC and the best action/adventure game the reviewer had seen.

In October 1992, the Shareware Industry Awards gave the series Best Entertainment Software and Best Overall. Sandy Petersen in Dragon called the series action games with hilarious graphics, acknowledging its debt to Super Mario Bros., and praised it as one of the best games of its type, not mindlessly hard, with humor in graphics and gameplay.

Legacy

Ideas from the Deep's first royalty check from Apogee in January 1991 for US$10,500 convinced them to leave Softdisk and work full-time on their own ideas. Hall and Wilbur feared being sued, but Romero and John Carmack dismissed the risk. John Carmack was confronted by Softdisk owner Al Vekovius, who had become suspicious of the group's behavior and had been told they were making their own games. Carmack admitted they had made Keen with Softdisk computers and planned to leave. Vekovius tried to form a partnership, but other employees threatened to quit if the team was rewarded for stealing. After weeks of negotiation, the Ideas team agreed to produce a series of games for Softdisk, one every two months, and on February 1 founded id Software.