Worms: Ultimate Mayhem is the definitive 3D Worms game! Load your weapons and experience a whole new dimension in destructive turn-based cartoon action! Taking the game into 3D creates all-new strategic and gameplay possibilities. With over 70 single-player missions and challenges, online and local multi-player for up to 4 players, 5 multi-player modes, Steam Achievements, unprecedented customization of both worms and weapons, and fully destructible environments, it’s bursting with anarchic mayhem. Battle and puzzle your way through all of the missions from both Worms 3D and Worms 4: Mayhem – it’s essentially two games in one. With the addition of HD visuals, gameplay enhancements and new extra content, it is the ultimate 3D Worms collection!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.