The battles haven't stopped raging in the kingdom! Invisible Threat contains three new episodes for true tower defense fans. We've spent more time on balancing the levels for Steam players. We've also added new enemies to diversify the game. You'll need to use new tactics to beat them! Features Wasteland – orcs have hidden amongst sharp and dangerous cliffs. Fiery Plateau – destroy all the enemies on a burning plateau. Mystic Valley – defend yourself against mystical creatures in an enchanted forest. Four new units, each with its own unique abilities - Skeleton, Necromancer, Fire Elemental, Nature Elemental. Four new achievements. Unique quests made specially for the new episodes. Challenge yourself with exciting trials!

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.