Speed run of Black Temple: Which bosses to kill?
You won't be able to skip any bosses in Black Temple. Well, maybe Na'jentus, but I've never tried, and honestly, he'll take you 30 seconds, as killing him would not require clearing any trash that you wouldn't need to clear just to get to Supremus.
The door to the Den of Mortal Delights will not open until Teron Gorefiend, the Shade of Akama, Gurtogg Bloodboil, and the Reliquary of Souls have all been defeated. Once you've defeated those, the door to Sharhaz's area unlocks, and it's a linear run upstairs, and Mother and the Council will both obstruct you unless killed.