You can purchase legitimate Steam keys for from the following stores: WinGameStore : Currently listed at $36.99. Humble Bundle : Available for $39.99.
: Features improved lighting, dynamic contrast, and support for DirectX 11. Minimum System Requirements According to the official Steam listing: OS : Windows 7 SP1 64bit / Windows 8.1 64bit Processor : Intel Core i3 2100 3.1GHz / AMD A8 3870 3.6GHz Memory : 4 GB RAM Graphics : NVIDIA GeForce GTX 465 / ATI Radeon HD 6870 Storage : 23 GB available space You can purchase legitimate Steam keys for from
If you want to see the gameplay differences and graphical enhancements in action before buying, check out these walkthroughs and technical showcases: Minimum System Requirements According to the official Steam
: Familiar "safe zones" are gone, and new enemy patterns force veteran players to relearn the game. and support for DirectX 11.