Hey there..
I'm not sure if this is a bug, but I've killed every single enemy on this level and I've found only 1 half of the key to the Illithid door...I have scoured the entire level for hours and I haven't seen the other half at all....can someone please tell me where each of the two halves of the key is? I only have the one that is found in the top left chamber of the Illithid encampment.
Thanks.

The other part is found in the bottom circular portion. You might want to hold down TAB as you go through that area, just to see if you missed it.

Thanks, I just went back and found it....I normally use TAB, but I found the second half behind the open door to the chamber...it was extremely hard to see because the door glows purple when you hit TAB....so the highlighted treasure was hidden which is very frustrating :)
Thanks though, for letting me know exactly where it was so I could go through the room meticulously. :)