Whispers in the Dark [Catacombs Level]
While walking through the Catacombs, ask every pc for a willpower test. Those who fail will have the urge to turn into a certain direction, following some path they were not following before. They do believe this is out of their own accord. Those who pass the test feel the urge as well but identify it as
something else but their own thought. A pc with the Psy-Trait who resist and passes an ordinary(+10) Psinisicience test can tell that this is a psionic lure. One level of success tells the pc that the source is intelligent and three tell the pc that it is daemonic.
If the pc follow the direction they are lured in they will soon face a large iron door, guarded by two combat servitors covered in strange symbols (Symbols of Wardings, as a ordinary(+10) test for Scholastic Lore (Occult) or Forbidden Lore (Daemonolgy) will tell any pc. The servitors will move threatingly and if the pc do not back off they will attack. Use stats given for combat servitors in the module, but heighten their AP by +2 against Psi-Power and they have +20 to resist any psy powers.
If the pc beat the servitors and open the door, they will find a small cave behind it where human female with blue skin and one central eye is chained against a wall, around her a half-circle of occult signs written in grey chalk (chalk mixed with the ashes of sacrifices). The female has a skin dotted with strange spikes, the fingers of both her hand are fused together and instead of feet the legs turn into rat-tail like tentacles at the point where a knee should be.
This is a daemonhost, calling itself Sabashya. It will thank the pc for coming and asking them to free it from the chains and to destroy the signs. In turn, it offers to lead the pc “to the place they want to reach, the Vault” and to “offer them help in gaining what they are after”. The pc freeing her will gain 1d10+2 points of corruption and must pass an opposed test of will (WP of Sabashya is 50). If the pc loses, Sabashya will simply teleport away in a flash of light. Otherwise, it will guide the pc and help them.
As the Archevist shows up, Sabasyha will cringe in fear. As the combat begins, the Archevist will spend three rounds-rebinding the host to her will. She knows its true name and was the one who bound the thing into the cave for being to much of a trouble to keep and to much of a danger to release.
I'm not sure I should even mention what this means in my local vernacular! I hope your game is R18.