The Walking Dead sells 8.5 million episodes

Telltale Games' critically lauded The Walking Dead has now sold more than 8.5 million episodes, thanks to a large upswing in public interest at the end of the year.

Speaking to the Wall Street Journal, Telltale CEO Dan Connors claimed that November and December 2012 were the series' biggest months in terms of sales, proving the unique strengths of the episodic model when applied to a licensed property.

""It was the culmination of the product, the game of the year awards, the retail push, and it still has a ton of head room in it," he said. "Apple has featured us a bunch of times for each of the episodes, and it's in Apple's Hall of Fame."

"we have all this momentum and recognition from the five months leading up to the Christmas launch. Then the finale happens, and bam, it's picked up by a much wider spread"

While the series' iOS sales only comprised 25 per cent of the total, mobile also showed the largest growth when compared to the company's previous releases. Mobile was also more reactive to interest in the TV show, the second season of which aired as the game episodes were being released.

"What we've done is have this online buzz going from April to November, and then have this finale to top it off and have that be the biggest event that propels it into the mass market," Connors added. "It allowed us to capture all that early adopter audience but also gives us the momentum to build a product that can reach out to the mass.

"Instead of paying a bunch of money to drive a bunch of installs, we have all this momentum and recognition that comes from all the work we've done over the five months leading up to the Christmas launch. Then the finale happens, and bam, it's picked up by a much wider spread."

The Walking Dead was Telltale's most expensive project to date, costing around 40 per cent more than a typical episodic project. At the time of writing, the game's average revenue per user is around $16.