i also have a question about this game, wich is about one of the abilities witht the guns. the revolver wich you can buy, has the ablity to throws coins, but i never knew what it did. i dont think i ever actually used it other than when i bought the gun to check out its abilities.
When you click on the gun in the shop to buy it, there's a piece of text that explains how it works. Basically, if you hit the coin while it's in the air, it will ricochet your shot into the nearest enemy's weakpoint.