Robot Entertainment ius four years old, and wants to give you a present. Visit the developer’s online store to benefit from 75% off unusual tower defence RPG Orcs Must Die, its sequel, Hero Academy and piles of DLC for all three titles. The offer is good for this weekend only, so get in before Monday rolls over the US. All games and DLC will activate through Steam, and Hero Academy is the only one available for Mac as well as PC. Robot Entertainment is an independent studio founded by former members of Age of Empires developer Ensemble Studios; it was the original team behind Age of Empires Online before handing over to Gas Powered Games.