ok so spread out and make sure you have collectors everywhere and a combination of mortars and defense laser things then spam the speed building the storage and then the reactors like craaaazy ive been on this survival with those and like 30 lasers and 15 mortars for the last hour or so
The key to endless is just to make a green factory at just the right spots on the very top you can fit rows of blue factory's and then what i did is i got hospital and then a tank factory and made the tanks amazing and i survived so far for over 30 minutes