Agree the ghost aiming is off, but the worst bug i have and happens a lot for me, are units just ghost through entire screen and go off the edge, doesnt count for a death but you cant finish the lvl because you havent killed all the units. I have 2 lvls left to get impossible badge and so far it has happened 5 times for me.
well for me i usually find these games extremely easy but cant win on hardest. Round with tanks they for some reason shoot over half the map and even with three different bazooka guys active at one time in cover, i have yet to kill a tank. They kill my guys before i even get a shot off. Agreed that one unit is cover is ridiculous. Though cant say cover does anything anyways.
wolfheat i had the same problem, you have to play story mode not free mode to make it to mars. I had 600,000 feet on my freaking second day with no mars.
as demchak said its all about bash towers, but i just mad a very small loop and only had two lvl 6 bash towers with a couple dmg boost next to them. Or you can juggle which is not that hard to do at all. By juggling you make to ends of your maze when they get close to one end you sell the turret at the other end and put one in to block their path making them go all the way around again. (anyone who won badges on the original one knows how to do it)