How do helpers work?

When a helper is active, the window that appears before the level starts displays the helper's icon and a timer showing the amount of time left before they are deactivated. While you play a level, the helper and their activation bar are displayed next to the game board. 

Winston the bulldog tosses a star booster onto the board when you fill his bar by making matches with blue gems.

The Black Cat grants you a lightning booster when you fill her bar by making matches with yellow gems.

Polly the parrot throws a blast booster onto the board when you fill her bar by making matches with red gems.

Horace the monkey tosses fireworks onto the board when you fill his bar by making matches with green gems.