Didn't know I'd be stuck in the caves, so I saved over my file when I entered. I have a level 3 laser. I've restarted from this save 3 times, because I can't build a good enough defense before the third wave of slimes (second wave from the left side) comes in and destroys all my ground level resources and elevators. The only way I survive the second wave is by building on that crystal platform, then all the slimes from the right side stay under it and don't move away. Once I lose my ground level, I cannot get rid of the slimes before the next wave comes in. Is there a strategy for me to get out of here, or do I need to start a new save from scratch?