Combo isn't that hard. Just stay mid (like for the 60-sec-don't-move-achievement-or-so) and skill 1 in Rapid Fire and all the rest in Fire Spread. Should get 1250+ Combo till level 4 ... (you also get the 1'000'000 points achievement this way on an easy way, without skilling even points).
Regards, Reefa
Very easy game for those who are smart enough. It reminds me on an old space shooting game more then ten years ago. Too bad I forgot the name, it is also good for our time now like Crillion.
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