It's hard to compete against "free."

Free-to-play and casual games finally took a big bite out of Activision Blizzard's (NASDAQ: ATVI) tent pole franchise, World of Warcraft. The subscription-based game lost 1.3 million members last quarter, or 14% of its total user base.

In the following video, Fool contributor Demitrios Kalogeropoulos says there's a sliver lining to this bad news, and that Activision has some levers it can pull to keep Warcraft afloat. Still, the best-case scenario is for a more steady decline for this aging game that will give the company time to build up its newer franchises.