Runic Games' popular action-RPG Torchlight has sold 1 million copies to-date across multiple platforms including the PC, Mac and Xbox 360. Runic Games sent word today that the game hit this milestone and confirmed that the sequel, Torchlight II, is on track for release in September or October of this year.

The original game was released in October 2009. Developer Runic Games followed it up with a Mac release in May 2010. Finally they released an Xbox Live Arcade version of the game in March of this year. Naturally the small development studios now owned by MMO maker Perfect World is pleased with the news.

Besides working on Torchlight II, Runic Games is developing a free-to-play MMO game set in the same universe. Torchlight II will feature a number of improvements including cooperative play, new overland areas, new classes, new weapons, magic, and more.

Formed in 2008 by veterans of the now-defunct outfit Flagship Studios, team members worked on Hellgate: London and Mythos during their tenure. Runic Games also includes a number of employees from Blizzard North, which created the original Diablo franchise.