If you're having a trouble with the jump over three platforms, start your jump on a platform that is a little higher than the oncoming so that you'll have some lift, and you'll have no trouble getting it. This is awesome! Good Game!
Word of Advice for the final boss. If you're having trouble staying on the platforms ( I know I was!) simply jump to the first one and then only use the up arrow key and touch nothing else. If you double jump right as the giant butterfly begins to shoot a laser towards you, you should have enough airtime to easily get over it. He should stay on the other side of the screen, shoot one beam below you, come up to your level, you jump above it and continue pummeling him to death.
Good hunting!
To Developer: I was on the final mission and Mozilla crashed. Now I do not have any saved games or anything. Unacceptable!!! Do i seriously have to playthrough the entire game again? I have all achievements minus the last.
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 "Ninja Run"){kind=icon}
 "The Breach"){kind=icon}
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 "Warfare: 1917"){kind=icon}
Hmmm.. maybe you should wait a bit longer...