Anyone else would've attack after being challenged like so, but Ben? Was more intrigued by the fact that she drew out a lightsaber. A real lightsaber. Sure, he'd seen energy weapons before, but nothing that was quit like this. It made his inner fanboy dance giddly around and for a moment, he forgot he was currently standing before her in the guise of Heat Blast and quickly approached, completely forgetting about the vampire that had tried to eat him just moments before.
"Whoa, cool!" He exclaimed, bending down so that he was about Jaina's height. "Dude, you actually have one of those? Man, they have been holding out on me! Last time I asked them if Jedi really existed, I was told to shut up and concentrate on the task at hand. Like I ever listen, but--wait. Is this some sort of joke? 'Cause if it is, I'm not going to be laughing, I'm--"
It was at that moment that the Omnitrix on Heat Blast's chest gave a flicker of red light, giving the lava creature enough time to let out a groan and an, "Aw, man!" before green light flashed and in it's place stood plain ol' Ben Tennyson.
He whacked the Omnitrix on his wrist with his other hand, glaring at it. Looking up at Jaina, he winced. "The plumbers are going to kill me," promptly slapping a hand to his forehead.