Gray Mann has built an unstoppable automaton army with a single purpose: to destroy all things Mann Co. Luckily for you, the majority of this robot legion is equipped with basic weaponry that could never level an entire building. Unluckily, they also have access to giant bombs, which they’d drag through hell if it meant dropping one in a Mann Co. bombhole. And it’s up to you to stop them. And it’s up to a small cadre of Special Robots to stop you from stopping the regular robots. – Official synopsis.