Flinch

Artemis Fowl II was a master of what gamblers called "a poker face."Butler had seen him face down dangers without so much as a sweat from as young as nine years of age. He didn't just pride himself on his ability to keep his cool, he considered a necessary tool in his various professions. Be it thief or philanthropist, you never let them see you flinch.That isn't to say he had no tells. Nothing that just anyone could pick up on, but Butler? Who had been with Artemis since his birth? He knew what to look for.