Voodoo Cannonball
From Monkey Island wiki
The Voodoo Cannonball is a magical item created by LeChuck, which he intended to use to blow down the walls of Elaine's fortress on Plunder Island at the beginning of The Curse of Monkey Island. A cannonball flaming with green Voodoo magic, it only manages to prove its destructiveness when Guybrush, trapped beneath deck, fires a cannon after having cut its restraint-rope. LeChuck drops the cannonball, which blows up, destroys his zombie form and causes the Death Starfish to capsize.
