As the subject says: looking for some help in turning the encounter/scenario below into a funnel that progresses into a 1st level adventure.
Black Pearl of Great Power
On the day of the new moon, the harbor of the mercantile city-state is
thrown into confusion when small boats moving through the harbor are
seized by thick tentacles belonging to 1d4 giant octopi and 1d6+2 giant
squid, the occupants of those boats dragged to a watery grave and then, as
soon as the attacks occur, the giant cephalopods disappear.
The next night of the new moon, chaos again erupts as those men and
women who were lost on that fateful night a month ago emerge from the
dark waters of the harbor, pale of skin, waterlogged and rotting, carrying
on their shoulders a cassone of black bronze and studded with coral
imbroglios of fiendish mermaids. Six wights, for wights they now are,
carry the cassone on poles of black bronze, while another twelve wights
serve as an honor guard, attacking anyone who comes near. This foul
procession is making its way to the grand temple of the sea god.
While this is happening, the giant octopi and squid are back in the
harbor, attacking ships and dragging sailors to their doom. Moments after
a sailor drowns, its body climbs from the harbor as a draug. The draug
run though the waterfront, killing indescriminately and spreading chaos
in their wake.
When the procession of wights reaches the grand temple, they will force
entry, set down their cassone before the idol of the sea god and open it.
From the cassone will arise dozens of thick, black tentacles, which will
grasp and throw down the idol of the sea god and replace it with a single,
large black pearl, an idol of Dagon, the new master of the mercantile