Just posting a quick spell I made to address that if anyone is interested including OP. Madness penalty is pretty high so you could tweak it but it is an unholy ritual afterall. You could also have the second head less of a demonic taint and more of a split personality as long as the spell was...
I ran the Oozing Temple so only far but I also made some larger changes. They found it pointing out of the Darklake, half drowned. I turned the whole place into a more direct Temple to Jubilex to hype up the demon infestation early in their adventure. I also infused the area with more faerzress...
Oh man. A SoB member is a very smart idea. Love the idea that a Society member sees the doom of the Demon Prince first hand and could potentially lead the PC's to some fun quests or locations.
Been running Oota and I accidentally mislabeled Hemeth a regular dwarf and not a duergar in the chaos of the sacrifice event at Shloppdeloopduhslup. So I rolled with it and made him a dwarf with fiery red hair, claiming the name Hemeth Fireblood who was going to sell a cargo of dwarf weapons to...