Ballade Cracker

Ballade Cracker (バラードクラッカー) is Ballade's special weapon in Mega Man IV. It can be shot in multiple directions, and explodes on impact. Ballade Cracker is also used by the "Bridge" boss. This is the weakness of Wily Robo Iron Golem's second form.

Ballade Cracker can also be obtained in Mega Man 10, Mega Man being the only playable character able to use it. In this game, it's a bit slower and it is Enker's weakness. 

Capacity
In Mega Man IV and Mega Man 10, two Ballade Crackers use 1 weapon energy unit. With a full weapon energy gauge, it can be used 38 times in Mega Man IV and 56 times in Mega Man 10.

Trivia

 * In Mega Man 10, the Ballade Cracker is the only weapon obtained from a boss that only one boss is weak against.
 * The Ballade Cracker is one of the only two weapons other than the Mega Buster that harms Enker (the other being the Mirror Buster) and the only weapon he is weak against.