North America and Europe's most played PC game of the last year was League of Legends, according to a report from DFC Intelligence. The study compiled records of social gaming service Xfire's more than 21 million users from July 1, 2011, to June 30, 2012, to determine that the free-to-play multiplayer online battle arena took the top spot, with almost 1.3 billion hours of activity.

League of Legends developer Riot Studios is LOLing all the way to the bank.

Diablo III, which was present for only 45 days--a bit more than a 10th--of the studied period, managed to claim fifth place with 172.9 million hours. World of Warcraft, another Blizzard title, saw a decline in user activity but still handily secured second place with 622.4 million user hours, and indie phenomenon Minecraft locked up third place with 371.6 million hours.

"The fact that online games such [as] League of Legends eclipsed more than a billion hours of online game time in a year is simply incredible," said DFC Intelligence CEO David Cole. He compared the figures to Bungie's April announcement, which revealed that Halo players had surpassed 2 billion hours of online matches since the release of Halo 2 in 2004.