finally got the impossible badge :D great game! but this targeting bug on ghosts nearly made me go crazy... needed the most tries for lvl 44, the ghost cutting the edges were absolute horrible if the tower suddenly stops shooting -.- try to slow down the whole field (slow lvl 4 + 2 range lvl 3), further use burst and anti air + sending units from left to right, good luck :)
how challenge 4 worked for me: set shield to follow the sword, keep the sword away from the dragon, if the dragon starts attacking the shield get closer with sword so its starts attacking but pay attention not to get closer to the dragon as the shield cause then the dragon will switch his attack on the sword... the bots AI is horrible as hell, same for the controls, further add a reset and stop button
if the shotgun or any further weapons actually got a clip-size it would be nice to manually control if you shot or not because sometimes you get the shotgun but there are less enemies and when the clip is empty the enemynumber raises, for my taste the track is too long by the possible upgrades at the moment i got demotivated to play it another time because i know i finished the track and thats it, well in the end i had my fun :) you did a good job till yet :D
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