The sequel fans have waited 16 years for is finally here - Sonic the Hedgehog 4 Episode I! Featuring enhanced gameplay elements, including the classic Sonic Spin Dash, and the versatile Homing Attack, Sonic the Hedgehog 4 Episode I picks up right where Sonic and Knuckles™ left off. Dr. Eggman’s back, and in an effort to finally rid himself of Sonic, he revisits – and improves – the very best of his creations. Get ready for the next chapter in an all new epic 2D saga built for old and new fans alike.

Go to: http://store.steampowered.com/ and download STEAM client Click "Install Steam" (from the upper right corner) Install and start application, login with your Account name and Password (create one if you don't have). Please follow these instructions to activate a new retail purchase on Steam: Launch Steam and log into your Steam account. Click the Games Menu. Choose Activate a Product on Steam... Follow the onscreen instructions to complete the process. After successful code verification go to the "MY GAMES" tab and start downloading.