Furious Mode: When you reach level 16 you will also unlock the Furious Mode, in which the orb rotates much faster than in the other available modes. The scoring system is slightly altered to give you more extra laps when doing combos.
Extreme Mode: When you reach level 20 you will also unlock the Extreme Mode, in which there is no Laps limitation but there are fewer spaces on the board to drop your orbs. The score multiplier also never goes back down during your session, it only goes up!