Swipe to move in that direction, collect checkered cubes to add 1 more bridge to build. If you're facing an edge, tap to build bridges, you will build in that line until you hit another ground block or run out of bridges to build. If you pick up a colored cube, that corresponding colored door will open up. A Brown box acts similarly to a sokoban box but if you push the box to the edge, it will get destroyed, and if you push it into a hole, the hole becomes a normal floor. Get to the goal to win. You can't lose.