it is definitely possible to beat classic mode by day 3.. you need all the upgrades in the shop and a little bit of luck.. start with your ramp as high as possible to get altitude 1 on your first jump. after the first level buy the pingu balloon and the plank with a couple hieght upgrades then the sugar rocket then some fuel then the glider and pulse jet..
when using the active skills remember hold it in to activate or just click to swap between skills. and please make a sandbox level it is so annoying nearly finished evolving everythin then i beat the game and had to go back like 5 launches
is there no way they could stop the lagging.. i had to leave the game at level 90 because it was just taking to long.. best tower defence game ever though