Tips on fighting the Warrens battle after leaving the basement?

Nerva

I know I can bypass fighting my way out of the Warrens, but hey, fighting is more fun, isn't it?

I've tried it a couple times though and got my party killed, so I looked around on the various online guides for info on the opponents and tactics to use, but didn't find anything. I'm wondering if the people here have any thoughts how to win this battle?

Zaxares

I managed it, but it was slow going and took a fair number of reloads. A big part of the problem is how if one enemy gets aggroed, it tends to draw in a whole bunch of nearby enemies, who then draw in other enemies etc. etc. My strategy was to try and bottleneck foes on the stairs, and then hurl debilitating and damaging AoE spells at archers and spellcasters up the back (Web and Cloudkill come HIGHLY recommended). If you have access to them, Confusion and Chaos spells also work wonders in drawing off enemy fire. Work your way up the tiers slowly, and watch out for the two Ogres; they hit VERY hard (they must have class levels!)