In Stage one it is possible to get 4 Stars in 2,3,6,8,9,10,12,20 and in Stage 2 in 1,3,4,8,9,10,11,12,13,18,20. So when you hit them all, you don't have to finish all levels for the hard badge ;) Truly, some need many tries :)
and for all complaining about the handling: I don't think it's very bad - you just have to adept to it. Tire upgrade indeed just increases the speed you have at the end of a race - but as it is quite often then that you overtake the last few cars, it's not that bad i think.
Overall an interesting concept, especially with the hit- and slalom challenges
oO you don't even have to complete the game for hard badge? well, i should have counted the events BEFORE trying to get gold for every challenge from the start
you don't even have to add double hp and one armor level, it's enough to add max. waves, 50% hp and double enemys (at least with ranged champ ~lvl 50). then you build first c,x and s,d,f and champ on top in mid. Then build many q-towers and a second f-tower and upgrade them to lightning towers -> ~270k damage delt
It's very easy... only max recharge, then Eagles and Dragons... do not increase initial mana. I did it like that and i "have to" heal my units because i have very much mana... and you can buy dragons after 20 seconds...
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