You hand your magic wand to your little helper, but you still have one in your hand. You say: "En Garde!" and start fencing with him!
When he gets the knack of it you surrender (before he injures you) and hand him your sword. Rather, wand. Then the wand goes off with a BANG and you really get scared and stick up your hands to surrender.
The BANG noise is created by a mechanism hidden in your hand.
