The next, and possibly most complicated puzzle of the game, involves a timed, pressure-sensitive gravity button and two boxes. Push the rightmost box up the right hill. In the process, you’ll set off the pressure-sensitive gravity button that reverses the orientation of gravity for the box on the left half of the room. This doesn’t matter yet. Keep chugging along and pushing that first box up the right hill. When it’s up as far as it can go, run back down, jump over the gravity button and use the remaining box to return to the high ledge to the left. When the first box returns to the bottom of the hill on its own, it’ll send that remaining box into the air. Because the ceiling is curved, the box will conveniently land to your left. Allow the gravity timer to run out and push it further left, underneath the previously inaccessible ladder to reach the second story.
On the right side of the second story is another ladder that, upon touching it, falls to the ground where the gravity button is located. Push the first box up the right hill again and climb the ladder back to the second story and run to the left to drag the gravity-reversed box onto the second level before it falls from the ceiling back to the first. One more time, push that first box up the right hill, climb the ladder and hop on the second story box. As soon as the gravity reverses, the box, along with your character, will be carried to the ceiling. Be sure to run to the right past the previously inaccessible door before you get caught between the ceiling and the box