Sentry Tower battle

[ntruhan]

Hello,
Trying to get through the Sentry Tower side-quest.
Got into the tower, past the spikes up the first set of stairs and past the 4 puzzle wheels on the floor.
However, once the door opens here there is a set of stairs that lead up to the hall that contains the glyphs.
From everything I read and a walkthrough I watched on youtube there shouldn't be anything in here,
but you run into a group of enemies with 3 shielded goblins and some kind of ghosted mage that respawns when you kill it and they kill me every time.

I know eventually I will get strong enough after enough levels to come back and do this, but these don't seem like they should be there.

Has anyone else run into these and have a strategy? Perhaps they were added as part of a patch?