In a world where teleportation magic doesn’t exist, the opportunity to travel a few days journey in moments is beyond value. With only a simple toll, you can be practically on the doorstep of Nizul-tibi before you know it.
During a storm the PCs come upon a little boy that plays in the rain. Upon further inspection they discover that he has one eye and a long tongue lolling in its mouth. Spit dripping. It is a demon from beyond that can access our realm during storms, it eats all heads that are not its own, living and dead.