When trying to find a match, start at the top and work downward. When you get a match at the bottom, potential matches at the top may split as the tiles drop. When a match is made, new tiles will fall to fill in the holes. In situations where this cannot happen (for example, under solid rock), random tiles will appear to fill the spaces. When making a match under a group of stones, quickly click the group before they fall to break the strata underneath.