Most likely dated information, but.......
I found it difficult to find the mirrors and ended up creating "Move2area" buttons on MCP for each mirror, as well as a "Move2area" button directly in front of the Dain (because everyone got stuck around the stairs and I died after killing everything-the suck). Incidentally for me, Hit Points for each door varied (1-3 million). --if anyone would like the grid coordinates I can post
As depicted below (not to scale, but rough estimate), I killed doors 1-3 & almost all adds on one side before proceeding to other side- **add spawns on other side (doors 4-6) only engage when in range**
Adds despawn on door 6 death. Usually had >6 on me, but ignored and burned the door down.
Killed the Advisor-i think, clicked MCP button to Dain (Base of stairs), made sure Tserrina (flying in the air wasn't targeted), then run up and talk to the Dain.
I did this encounter more times than I care to admit before creating my move2area buttons. After that, it was a one-time go!
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