Dex was not expecting that, he also was not expecting Zara to not pick up his scent yet. Regardless, now is when Dex decides to reveal himself for what he is. Thing is he has a plan now, and he promptly sits on the snout of the Wyvren "Well, well, well...Aren't you a big girl" He cheerfully says as he sits "Say new pal...Wanna play a game?" Its not yet an obvious trick