This achievement is very easy to get when you're inside of the flying ships. This will be after the flying carpet section, and after the part where you're running along the tops of the ships.
When you get to the first bad guy that throws grenades at you kill him and then stand on the platform he was on. There will now be an infinite number of enemies that spawn and run in from the left and right sides of the screen. Just keep flipping the blocks as they run in front of them until your achievement pops.