You receive explosive power-ups in match-3 levels every time you make a combination of four or more pieces. Here are the power-ups available in the game:
Firecrackers explode everything within a one-tile radius, and you can get them by matching four pieces of the same color.
Bombs explode everything within a two-tile radius, and you can get them by matching five pieces of the same color.
Dynamite explodes everything within a three-tile radius, and you can get it by matching six pieces of the same color.
Warheads explode everything within a four-tile radius, and you can get them by matching seven or more pieces.
Lightning removes all the pieces of the same color from the field, and you can get it by using the other power-ups.