MSI Giving Away Loads of Hardware in Tower Defense Contest
You also have to join MSI's fan club. Once you've done that, and after you play the game, provide your contact information to be entered in various MSI prize drawings. Bear in mind that your combat results will be automatically shared on your Facebook wall, which MSI spins as a way "to showcase your brilliant tactical strategies and challenge your friends."
As with any contest, there are several terms and conditions to note, all of which you can check out here. Good luck to those of you who enter!