Fireworks is a reoccurring object that appears throughout the series.
Fireworks appears in this game as a rather important side item. Fireworks can be bought from a mole in Moleville for 500 coins. The Fireworks can then be traded for the Shiny Stone which then can unlock the door in Monstro Town in order to fight Culex. Multiple Fireworks can be purchased which will be used at the end of the parade at the end of the game.