Donald R. Kaye (June 27, 1938 - January 31, 1975), co-founder of TSR, Inc., was the childhood friend of Gary Gygax, and shared an interest in war games and tabletop miniatures with him during their youth. When Gygax was co-developing the game that would become known as Dungeons & Dragons (D&D) in 1972, Kaye played in the second-ever session; his character Murlynd was one of the first D&D characters created as well as one of the earliest explorers of the dungeons under Gygax's Castle Greyhawk. Kaye and Gygax became convinced that D&D and similar games were an excellent business opportunity, and together they founded TSR, Inc. in 1973. However, only two years later, just as sales of D&D started to increase exponentially, Kaye unexpectedly died of a heart attack at age 36. With no provision made for a partner's death, the stage was set for Gygax to lose control of TSR and ultimately be forced out of the company a decade later.
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