While you were out cruising through outer space, you ran out of gas and crash-landed on planet Gravitron. Your ship's in good shape, and in each level you're given the chance to collect fuel so you can get off the planet and fly back home. To beat a level, figure out how to open the door to the transporter and get in. You're given a box to weigh down the platform that opens the door to the transporter, and you can control gravity, which allows you to walk on the ceiling and walls. Move objects and change gravity in the right order to pick up the gas cans and get through the transporter door.