Night Guard's Musket

Equipped creature gets +1/+1, has vigilance, and has "{t}: If Night Guard's Musket doesn't have a charge counter on it, put a charge counter on it. Activate this ability only any time you could cast a sorcery."
Whenever equipped creature attacks, you may remove a charge counter from Night Guard's Musket. If you do, destroy target creature.
Equip {2}