Sharp Knuckle

Sharp Knuckle is the Special Weapon used by the Roboticized Master Knuckles Man in the crossover Worlds Collide. The weapon is essentially a spike-enhanced super punch, and when used by Knuckles Man it proved capable of deflecting the Rapid Stinger and shattering the sound energy of the Acoustic Blaster. It was broken by the Piko Hammer however, allowing Mega Man to restore Knuckles the Echidna to normal.

While the weapon has not been used against any of the Roboticized Masters, there is a chance, given the order of combat shown in the comic, that it is the weakness of Vector Man.