Crystal Skull location?

In my NG+ run I’ve been working on filling out the compendium and to put a long story short the last one I need is the crystal skull treasure demon. I’ve looked routinely through floors 12 - 14 in the path of Sheriruth and all of the path of Da’at with treasure traps but all I run into is emperors amulet, regent and sometimes hope diamond. I ran into it once on 12/24 but it managed to run away before I could get it. Any advice on how to get it would really help. Cheers