Taran Zhu, lord of the Shado-pan.
To be honest when I met him first time he looked awesome for me, a lord of a ninja elite forces on Pandaria.
But the only problem was that in the time progression my excitation of him was going down.
He was sending his students to fight instead of doing that himself(daily quests), he was possessed by the Sha of Anger, eventually he lost his fight with Garrosh, who almost kill him. In the end he spared Warchief life and got him on the Trail of Pandaria,[SPOILER] and then he escaped.
The potential of this character was totally wasted for me, the only "badass" thing he said is:
"Your father dabbled in powers beyond reckoning. Where is he now?" (in the alternate timeline on the Draenor, duh?)
What do you guys think?