Buy the first 4-5 Levels ONLY health potions (get at least 60, for 50$ and 150$). That will save alot cash for later. You can save your money for the last bow(250k$), just buy armor. You can win without using spells, bombs, swords ect. Buying arrows is not necessary. You can spend 11 Bow upgrade points, save the rest to max. out the last bow.
cheers
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