There are 5 (or 6) demon knights and they are all pretty tough. They have high MR and can all cast Power Word Kill so make sure your HPs don't drop below 60 for your tanks. There are a few tactics for this. The semi-cheezy one is to lure them out to the bridge just outside that room and fight them one-on-one. If you decide to stay in the room, make sure you have lots of summonings blocking the way between you and them. They will appear in the corners of the room so buff up your tanks and try to concentrate on killing one at a time. The spell Lower Resistance and Greater Malison really come in handy here.
One thing: your druid will max out at Level 14, unfortunately, they did not support the druid powers beyond level 14 for BG2. For ToB they have (sort of).
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