This is tip 3 of 4 for Bubble Witch 2 Saga 117.
Level 117 Cheat #3: Interchange bubbles in the shooter.
When you think you have no other option, don’t forget to see what the upcoming bubble is. Switching the bubbles in the shooter may help you to make your way to the top more effectively. You do not want to clog up your board with unnecessary bubbles. This will make your life much harder later in the game. Having bubbles with no combination possibilities will waste your moves that you will need to reach the top.