New Infinities Productions, Inc.
In late 1985, Gary Gygax and Lorraine Williams vied for control of TSR, which eventually resulted in Gygax's ouster. Mentzer, who had worked closely with Gygax for six years and shared his vision of the direction for D&D, was unwilling to work for Williams, and left TSR in 1986.
Gygax quickly formed New Infinities Productions, Inc. (NIPI) to create new products for the role-playing game market, and Mentzer joined as Design Executive. Mentzer, together with Gygax and Kim Mohan, formed the Creative Committee.
The company's first product was the science fiction-themed Cyborg Commando, co-written by Mentzer and Gygax, and published in 1987. The next project a was a new fantasy role-playing game spanning multiple genres called Dangerous Journeys. (It was originally to have been called Dangerous Dimensions, but the name was changed to Dangerous Journeys in response to a threat of a lawsuit from TSR, Inc. that the DD abbreviation would be too similar to "D&D.") When the product was released by Game Designers' Workshop, TSR immediately sued for copyright infringement. The suit was eventually settled out of court, with TSR buying the complete rights to the Dangerous Journeys system from New Infinities and then permanently shelving the entire project. This led to the demise of NIPI, and Mentzer decided to leave the game industry.
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