Alright, to get the swans, you need a large amount of luck to begin with. Also it helps to buy all the upgrades except the beacon one, because it makes it really hard to avoid getting the geese. Also, if you do not get the achievement by the time you cross the second ocean, you should consider suicide and a restart.
WOW, sometimes this doesn't wuite load right, i keep getting a gray screen, but after a few beers, i managed to make it to level 73.8... the hidden bonus level where you fight a rick roll, priceless.
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