your the closet to quoting the Tooltip for the ability....
its says and i quote
"" Slams into the Target with a Rocket-Propelled shoulder charge, dealing 3502 - 3535 Kinetic damage to weak or standard targets and 2517 - 2549 knetic damage to Strong targets, only works on incapacitated targets""
(no where in the tool tip does it say non-boss, non-champion, non-player, Now having said that i kinda got that impression when i tried to use it.. however as i said in the OP. my Assassin can use his Mirror Ability in pvp.
that was how my question was posed. why can assassins use theirs...and Bounty Hunters cannot. cause i mean thats a rocket punch.. it normally crits for 5-6k dmg. for me.
Assassins cannot use Tumult in warzones. I have no idea where you got the crazy idea that you can.