The way I got to 3,000,000 feet or higher is save up for Tank and the Last Tier ( Gun ), then go play some levels until you get about 1,000,000 cash ( will take a while since you get about 100,000-200,000 cash a game ) then buy about 150x nukes. This should help you get the Hard badge.
Lolz, I know this is considered cheating but you can get the challenge by doing two players. I didn't cheat, I played with my sister, but I know you guys are going to play two players by yourself to get the challenge. XD. + so everyone can see this.
Seriosly, I don't think the game needs badges. How would you expect it to have badges anyway? Hit 3rd stage ( Medium - 15 points ) or Get 10x combo or higher ( Hard - 30 points ). Seriosly? So stop posting comments like " + if you think this game needs badges! " It really gets annoying.
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