Blackrock spire 1st boss

The 1st boss of blackrock spire:Pyrouguard emberseer won't start the fight....you are supposed to click on the blackrock altar stone tablet and than all the adds in the room attack you,after you kill them all after a while the boss should be attackble,but i tryed clicking over 100 times and nothing happends still,any suggestion?

I also waiting for answer for this!

Just click on it, and walk up to the boss platform. It should work.

Seem to be bugged
I did kill all adds then click altar stone but boss can't be attacked
So I'm stuck