Author David Craddock, who is researching a book on developer Blizzard North, claims to have learned that a handheld version of the RPG called Diablo Junior was in the works.
"Following Diablo 2′s release, Blizzard North split into two teams… kind of," Craddock told ShackNews. "One team immediately started in on Diablo 2′s expansion set, Lord of Destruction. The other team went into spitball mode, kicking around ideas for a new IP.
"But several other developers ventured into groups of two or three and put together proposals for smaller projects.
"One of those was given the working title Diablo Junior, a game tentatively planned for the Game Boy Colour and/or the Game Boy Advance, depending on market share and other business-y factors."
The author went on to say that Blizzard planned on putting Diablo Junior out on three cartridges, each containing a different playable hero, in a move inspired by the Pokemon series.
"Heroes started in a unique town before heading into dungeons and wilderness zones. Diablo Junior was ultimately put out to pasture [absent of cow levels, I'm sure] because of the steep production costs associated with developing handheld games," he added.
Diablo 3 was released for PC in May, selling 10 million copies in less than three months.
Watch gameplay footage from the original Diablo below: