Power
The Boy had the power to destroy the universe with a word.
"Give me your wallet", said the mugger.
"You should be nice to me", said the Boy. "I can destroy the universe with a single word."
"Hah! What word?" asked the mugger.
The Boy spelled it aloud, because he couldn't say it.
"That's stupid", said the mugger, after sounding out the word, then repeating it a few times. "See, nothing happened."
"It's only when I say it."
"So go ahead", taunted the criminal.
"But... I don't want to destroy the universe!"
"Then give me your wallet, or I'll destroy you."
Suddenly the Boy felt completely powerless.