General Ortol from SWTOR, the final and greatest challenge of the Cademimu Flashpoint. Or as I like to refer to him, 'General Poor Volume Control'. The guy sure likes to yell at the top of his lungs for everything, and thankfully that helps tip you off when the extremely lethal missiles in his chamber are about to start firing.
As I found out recently however, that's no guarantee of safety once 3/4 of the room is filled with exhaust blasts and he starts using Area of Effect knockback to try and drive you into it. I've beaten him flawlessly once, but the rest of the time your party will probably wipe several times before getting the hang of him even if you were perfect up until then.
The game has way harder bosses, but he's the earliest hard one IMO. Just wish he'd use lines from A Few Good Men before dying.