I was only lvl 9 when I beat the "secret lvl". This game was way to easy. I beat all the lvls on my first try except for lvl 6 and 1. :) I was a paladin while only upgrading strength.
The trick to winning all levels is to make sure under every building is a newsstand. DO NOT make any benches or anything else. Later make a bus stop. Upgrade the buildings from cheapest to most expensive.
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