https://www.sageadvice.eu/how-viable-would-it-be-for-an-evil-cult-bhaal-bane-or-myrkul-to-set-up-a-shrine-temple-in-the-waterdeep-sewers/
How viable would it be for an evil cult (Bhaal, Bane, or Myrkul) to set up a shrine/temple in the Waterdeep sewers?