If you purchased Torchlight from Runic Games via torchlightgame.com or Perfect World via perfectworld.com before May 19, 2010, you may add it to Steam. Note: Please remove previously installed versions of Torchlight before proceeding.
Here's how:
- From Steam, navigate to the Games menu.
- Choose Activate a Product on Steam…
- Follow the prompts.
At this point, Torchlight will be activated and should automatically begin downloading. Once this is complete, you can run it from your Steam library by clicking Play, or by double-clicking it from the list.