I've Lost My Rifle
A group of soldiers are preparing for an attack from the enemy, when a private walks up to the captain and says "Captain, I've lost my rifle! What do I do?"
The captain thinks for a moment, then grabs a broom and hands it to the private. He says "If any enemies show themselves, just point this at them and shout "Bangity bangity bang." The private argues about how it won't work, but the captain insists until he finally gives up. "Well what about close quarters then?" says the private. The captain thinks for a moment, then takes a butter knife and sticks it to the end of the broom He then says "If they come close, just use this and say "stabbity stabbity stab" The private doesn't even bother arguing this time.
The next day, the enemy mounts a huge offensive. There is an immense army. The private starts aiming his broom and saying "Bangity bangity bang," and it actually proves effective. This guy starts mowing down the enemy soldiers with his broom, but there's just so many, and they start charging him. So he starts to "stabbity stabbity stab," and the soldiers drop in front of him bleeding.
After some time, there is no one left alive on the battlefield but him. There are corpses from both sides everywhere. Except there is one enemy soldier in the distance. The enemy soldier is not aiming a gun or anything. He is simply walking towards the broom wielding soldier while mumbling something. The soldier aims his broom and fires, but to no effect. He continues trying over and over, but the enemy soldier just walks towards him, still mumbling. The soldier gets close, and he tries stabbing, but it still has no effect. The soldier finally reaches him, and simply pushes him over. He literally crushes him just walking over him. As his life fades, he finally hears the enemy soldier walking off saying "Tankity tankity tank."