What's with the lever the opens the vertical sewer shaft, near the bottom right of the sewers. You can only get there from that side of the map anyway. Only thing is that it can be glitched so that you need to restart map to open sewer.
Even if you follow the walkthroughs, on some levels you still lose. Then do the exact same thing, you still lose. Try it a 3rd time, and you somehow win. In other words the tower targeting, esp. with ghosts, IS COMPLETELY RANDOM.
Putting ghost towers into a mega tower is awful since it destroys their 'ghost killing' powers and just gives them crappy attack. ANd putting area/boost things into mega tower only affect the tower, not the area around them.
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