Go in search of the tombs of King Cool! Put your jetpack on and set out: you'll have to avoid all kinds of obstacles, but there are also coins and bonuses. As soon as you hit an obstacle, you must go back in time. Keep an eye on your jetpack's fuel and also on the amount of 'back-in-time sand' you have.
Up and down arrows = move up and down;
Left arrow = go back in time;
Right arrow = fast forward.