Played some of the UDK game, Dungeon defense.
Nice simple tower defence game, with a cool action-RPG element. You place your structures with the money you receive in the build phase and during the defending phase, you must attack the monsters with your main character to help protect the crystal at your base.
Very enjoyable, I will definitely play more later. I didn't get very far the first time, but that is through no fault of the game, it's all to do with me being rubbish :D.
