Wrathion cannot honestly say he has spent time in Westfall, but he has at least travelled through it on occasion to get to other, more interesting places.

That's enough to, at a glance, recognise its unusual features.

"Be on your guard," he advises gently, "remember, this could be hiding more traps."

Anduin would no doubt be frustrated if he walked himself into a trap and had to be cut down. Neither of them are fond of anything close to the sensation of failure or embarrassment.