Spooky DnD One-Shot Adventure - Spooky

The characters are members of a faction gathering for an initiation. A character is a shapechanger.
It is at an underground vault which is used to hold a herd of goats.
There are ogres preparing a sacrifice. And a vengeful warlock seeks to burn everything to the ground.
At some point a deity sends a sign.
As the adventure progresses a portal slowly starts to open

The characters are a group of caravan guards protecting a single merchant, stopping here for the night.
It is at a treetop village in the woods which is influenced by a plane of fire.
There are a group of grells holding a funeral. And a vengeful warlock seeks to burn everything to the ground.
At some point there are wolf howls.
As the adventure progresses more and more zombies start to approach

The characters are a group of inventors gathered for a special exhibition.
It is at a library of forbidden knowledge which is cursed by a deity.
There are myconids creating a strange garden. And a crazy priest seeks to defeat a repulsive diviner.
At some point a portal to another realm opens.
As the adventure progresses there is a series of murders

The characters are working for the local ruler hunting a criminal. A character is a shapechanger.
It is at a foreboding cloud castle which has many strange lights.
There are kuo-toa worshipping many-eyed creatures. And a few creatures are inhabited by intellect devourers who seek new hosts.
At some point a planar portal opens.
As the adventure progresses people start to gather for a funeral

The characters are a group of ghost investigators with a covered wagon, investigating a mystery.
It is at a night market which has a crossing to another part of the world.
There are a variety of kobolds, sprites and other small-sized creatures, scavenging what they can. And a famous artist is trying to finish a masterpiece by morning.
At some point a portal to another realm opens.
As the adventure progresses signs of an apocalypse manifest