The Walking Dead has been one of this year's surprise critical hits, reviving the adventure genre and the zombie trope that both seemed stuck in a rut. It's put a spring in Telltale's step with strong sales, too, after the Jurassic Park game was roundly panned. So just how much has Telltale's zombie-adventure game sold?

In a Wall Street Journal interview, CEO Dan Connors says the game has sold 8.5 million episodes. That "episodes" distinction is important, since the game's first season is split into five parts. That means the staggering number is inflated a bit since it's not a count of unique players. But even if everyone bought all five episodes (which is unlikely), it would mean 1.7 million people have played the game. Almost 2 million as a minimum number of unique players is nothing to sneeze at.

Connors noted that it's been on sale since April, but November and December were its biggest months due to critical buzz and the series finishing its first season run. It also had the advantage of entering Apple's "Hall of Fame" for gaming apps, and Connors says that's paid off. The game has earned about 25% of its revenue through the iOS platform, and that version is currently on the largest upswing of any platform.