Feed the 'hungry shapes' by dropping same-shaped pieces on them. The piece you're dropping can be a different color than the 'hungry shapes,' but they gotta be the same shape. If you drop a piece that's a different shape, it won't get eaten, and you'll lose a life. As you level up, things get trickier with more 'hungry shapes,' their positions swapping around, quicker drop speed, and different colors of the same shapes.