Robots are coming from every direction. You have a mere 60 seconds to reinforce your stronghold OR to spend on looking for weapon upgrades and health items. What do you prefer?
This game is a badly optimized mess at the moment, which is why there isn't a link to the executable file right here. It should be here someday when I fully complete the game. If that ever happens of course.
The game is insanely difficult and designed to be almost frustratingly hard, until you get the hang of it. Survive for as long as you can and score as many points as you possibly can.